Data Scientist Papers A-Z

A
Paper 1603-2015:
A Model Family for Hierarchical Data with Combined Normal and Conjugate Random Effects
Non-Gaussian outcomes are often modeled using members of the so-called exponential family. Notorious members are the Bernoulli model for binary data, leading to logistic regression, and the Poisson model for count data, leading to Poisson regression. Two of the main reasons for extending this family are (1) the occurrence of overdispersion, meaning that the variability in the data is not adequately described by the models, which often exhibit a prescribed mean-variance link, and (2) the accommodation of hierarchical structure in the data, stemming from clustering in the data which, in turn, might result from repeatedly measuring the outcome, for various members of the same family, and so on. The first issue is dealt with through a variety of overdispersion models such as the beta-binomial model for grouped binary data and the negative-binomial model for counts. Clustering is often accommodated through the inclusion of random subject-specific effects. Though not always, one conventionally assumes such random effects to be normally distributed. While both of these phenomena might occur simultaneously, models combining them are uncommon. This paper proposes a broad class of generalized linear models accommodating overdispersion and clustering through two separate sets of random effects. We place particular emphasis on so-called conjugate random effects at the level of the mean for the first aspect and normal random effects embedded within the linear predictor for the second aspect, even though our family is more general. The binary, count, and time-to-event cases are given particular emphasis. Apart from model formulation, we present an overview of estimation methods, and then settle for maximum likelihood estimation with analytic-numerical integration. Implications for the derivation of marginal correlations functions are discussed. The methodology is applied to data from a study of epileptic seizures, a clinical trial for a toenail infection named onychomycosis, and survival data in children with asthma.
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Geert Molenberghs, Universiteit Hasselt & KU Leuven
Paper 2641-2015:
A New Method of Using Polytomous Independent Variables with Many Levels for the Binary Outcome of Big Data Analysis
In big data, many variables are polytomous with many levels. The common method to deal with polytomous independent variables is to use a series of design variables, which correspond to the option class or by in the polytomous independent variable in PROC LOGISTIC, if the outcome is binary. If big data has many polytomous independent variables with many levels, using design variables makes the analysis processing very complicated in both computation time and result, which might provide little help on the prediction of outcome. This paper presents a new simple method for logistic regression with polytomous independent variables in big data analysis when analysis of big data is required. In the proposed method, the first step is to conduct an iteration statistical analysis from a SAS® macro program. Similar to an algorithm in the creation of spline variables, this analysis searches for the proper aggregation groups with a statistical significant difference from all levels in a polytomous independent variable. In the SAS macro program for an iteration, processing of searching new level groups with statistical significant differences has been developed. The first is from level 1 with the smallest value of the outcome means. Then we can conduct a statistical test for the level 1 group with the level 2 group with the second smallest value of outcome mean. If these two groups have a statistical significant difference, we can start to test the level 2 group with the level 3 group. If level 1 and level 2 do not have a statistical significant difference, we can combine them into a new level group 1. Then we are going to test the new level group 1 with level 3. The processing continues until all the levels have been tested. Then we can replace the original level values of the polytomous variable by the new level values with the statistical significant difference. In this situation, the polytomous variable with new levels can be described by these means of all new levels because of the 1 to 1 equivalence relationship of a piecewise function in logit from the polytomous's levels to outcome means. It is very easy to approve that the conditional mean of an outcome y given a polytomous variable x is a very good approximation based on the maximum likelihood analysis. Compared with design variables, the new piecewise variable based on the information of all levels as a single independent variable can capture the impact of all levels in a much simpler way. We have used this method in the predictive models of customer attrition on the polytomous variables: state, business type, customer claim type, and so on. All of these polytomous variables show significant improvement on the prediction of customer attrition than without using them or using design variables in the model development.
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jian gao, constant contact
jesse harriot, constant contact
lisa Pimentel, constant contact
Paper 2141-2015:
A SAS® Macro to Compare Predictive Values of Diagnostic Tests
Medical tests are used for various purposes including diagnosis, prognosis, risk assessment and screening. Statistical methodology is used often to evaluate such types of tests, most frequent measures used for binary data being sensitivity, specificity, positive and negative predictive values. An important goal in diagnostic medicine research is to estimate and compare the accuracies of such tests. In this paper I give a gentle introduction to measures of diagnostic test accuracy and introduce a SAS® macro to calculate generalized score statistic and weighted generalized score statistic for comparison of predictive values using formula's generalized and proposed by Andrzej S. Kosinski.
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Lovedeep Gondara, University of Illinois Springfield
Paper 2980-2015:
A Set of SAS® Macros for Generating Survival Analysis Reports for Lifetime Data with or without Competing Risks
The paper introduces users to how they can use a set of SAS® macros, %LIFETEST and %LIFETESTEXPORT, to generate survival analysis reports for data with or without competing risks. The macros provide a wrapper of PROC LIFETEST and an enhanced version of the SAS autocall macro %CIF to give users an easy-to-use interface to report both survival estimates and cumulative incidence estimates in a unified way. The macros also provide a number of parameters to enable users to flexibly adjust how the final reports should look without the need to manually input or format the final reports.
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Zhen-Huan Hu, Medical College of Wisconsin
Paper 3311-2015:
Adaptive Randomization Using PROC MCMC
Based on work by Thall et al. (2012), we implement a method for randomizing patients in a Phase II trial. We accumulate evidence that identifies which dose(s) of a cancer treatment provide the most desirable profile, per a matrix of efficacy and toxicity combinations rated by expert oncologists (0-100). Experts also define the region of Good utility scores and criteria of dose inclusion based on toxicity and efficacy performance. Each patient is rated for efficacy and toxicity at a specified time point. Simulation work is done mainly using PROC MCMC in which priors and likelihood function for joint outcomes of efficacy and toxicity are defined to generate posteriors. Resulting joint probabilities for doses that meet the inclusion criteria are used to calculate the mean utility and probability of having Good utility scores. Adaptive randomization probabilities are proportional to the probabilities of having Good utility scores. A final decision of the optimal dose will be made at the end of the Phase II trial.
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Qianyi Huang, McDougall Scientific Ltd.
John Amrhein, McDougall Scientific Ltd.
Paper SAS2603-2015:
Addressing AML Regulatory Pressures by Creating Customer Risk Rating Models with Ordinal Logistic Regression
With increasing regulatory emphasis on using more scientific statistical processes and procedures in the Bank Secrecy Act/Anti-Money Laundering (BSA/AML) compliance space, financial institutions are being pressured to replace their heuristic, rule-based customer risk rating models with well-established, academically supported, statistically based models. As part of their customer-enhanced due diligence, firms are expected to both rate and monitor every customer for the overall risk that the customer poses. Firms with ineffective customer risk rating models can face regulatory enforcement actions such as matters requiring attention (MRAs); the Office of the Comptroller of the Currency (OCC) can issue consent orders for federally chartered banks; and the Federal Deposit Insurance Corporation (FDIC) can take similar actions against state-chartered banks. Although there is a reasonable amount of information available that discusses the use of statistically based models and adherence to the OCC bulletin Supervisory Guidance on Model Risk Management (OCC 2011-12), there is only limited material about the specific statistical techniques that financial institutions can use to rate customer risk. This paper discusses some of these techniques; compares heuristic, rule-based models and statistically based models; and suggests ordinal logistic regression as an effective statistical modeling technique for assessing customer BSA/AML compliance risk. In discussing the ordinal logistic regression model, the paper addresses data quality and the selection of customer risk attributes, as well as the importance of following the OCC's key concepts for developing and managing an effective model risk management framework. Many statistical models can be used to assign customer risk, but logistic regression, and in this case ordinal logistic regression, is a fairly common and robust statistical method of assigning customers to ordered classifications (such as Low, Medium, High-Low, High-Medium, and High-High risk). Using ordinal logistic regression, a financial institution can create a customer risk rating model that is effective in assigning risk, justifiable to regulators, and relatively easy to update, validate, and maintain.
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Edwin Rivera, SAS
Jim West, SAS
Paper SAS1919-2015:
Advanced Techniques for Fitting Mixed Models Using SAS/STAT® Software
Fitting mixed models to complicated data, such as data that include multiple sources of variation, can be a daunting task. SAS/STAT® software offers several procedures and approaches for fitting mixed models. This paper provides guidance on how to overcome obstacles that commonly occur when you fit mixed models using the MIXED and GLIMMIX procedures. Examples are used to showcase procedure options and programming techniques that can help you overcome difficult data and modeling situations.
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Kathleen Kiernan, SAS
Paper 3492-2015:
Alien Nation: Text Analysis of UFO Sightings in the US Using SAS® Enterprise Miner™ 13.1
Are we alone in this universe? This is a question that undoubtedly passes through every mind several times during a lifetime. We often hear a lot of stories about close encounters, Unidentified Flying Object (UFO) sightings and other mysterious things, but we lack the documented evidence for analysis on this topic. UFOs have been a matter of interest in the public for a long time. The objective of this paper is to analyze one database that has a collection of documented reports of UFO sightings to uncover any fascinating story related to the data. Using SAS® Enterprise Miner™ 13.1, the powerful capabilities of text analytics and topic mining are leveraged to summarize the associations between reported sightings. We used PROC GEOCODE to convert addresses of sightings to the locations on the map. Then we used PROC GMAP procedure to produce a heat map to represent the frequency of the sightings in various locations. The GEOCODE procedure converts address data to geographic coordinates (latitude and longitude values). These geographic coordinates can then be used on a map to calculate distances or to perform spatial analysis. On preliminary analysis of the data associated with sightings, it was found that the most popular words associated with UFOs tell us about their shapes, formations, movements, and colors. The Text Profiler node in SAS Enterprise Miner 13.1 was leveraged to build a model and cluster the data into different levels of segment variable. We also explain how the opinions about the UFO sightings change over time using Text Profiling. Further, this analysis uses the Text Profile node to find interesting terms or topics that were used to describe the UFO sightings. Based on the feedback received at SAS® analytics conference, we plan to incorporate a technique to filter duplicate comments and include weather in that location.
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Pradeep Reddy Kalakota, Federal Home Loan Bank of Desmoines
Naresh Abburi, Oklahoma State University
Goutam Chakraborty, Oklahoma State University
Zabiulla Mohammed, Oklahoma State University
Paper 3412-2015:
Alternative Methods of Regression When Ordinary Least Squares Regression Is Not Right
Ordinary least squares regression is one of the most widely used statistical methods. However, it is a parametric model and relies on assumptions that are often not met. Alternative methods of regression for continuous dependent variables relax these assumptions in various ways. This paper explores procedures such as QUANTREG, ADAPTIVEREG, and TRANSREG for these kinds of data.
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Peter Flom, Peter Flom Consulting
Paper 3371-2015:
An Application of the DEA Optimization Methodology to Make More Effective and Efficient Collection Calls
In our management and collection area, there was no methodology that provided the optimal number of collection calls to get the customer to make the minimum payment of his or her financial obligation. We wanted to determine the optimal number of calls using the data envelopment analysis (DEA) optimization methodology. Using this methodology, we obtained results that positively impacted the way our customers were contacted. We can maintain a healthy bank and customer relationship, keep management and collection at an operational level, and obtain a more effective and efficient portfolio recovery. The DEA optimization methodology has been successfully used in various fields of manufacturing production. It has solved multi-criteria optimization problems, but it has not been commonly used in the financial sector, especially in the collection area. This methodology requires specialized software, such as SAS® Enterprise Guide® and its robust optimization. In this presentation, we present the PROC OPTMODEL and show how to formulate the optimization problem, create the programming, and process the data available.
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Jenny Lancheros, Banco Colpatria Of ScotiaBank Group
Ana Nieto, Banco Colpatria of Scotiabank Group
Paper 3300-2015:
An Empirical Comparison of Multiple Imputation Approaches for Treating Missing Data in Observational Studies
Missing data are a common and significant problem that researchers and data analysts encounter in applied research. Because most statistical procedures require complete data, missing data can substantially affect the analysis and the interpretation of results if left untreated. Methods to treat missing data have been developed so that missing values are imputed and analyses can be conducted using standard statistical procedures. Among these missing data methods, multiple imputation has received considerable attention and its effectiveness has been explored (for example, in the context of survey and longitudinal research). This paper compares four multiple imputation approaches for treating missing continuous covariate data under MCAR, MAR, and NMAR assumptions, in the context of propensity score analysis and observational studies. The comparison of the four MI approaches in terms of bias in parameter estimates, Type I error rates, and statistical power is presented. In addition, complete case analysis (listwise deletion) is presented as the default analysis that would be conducted if missing data are not treated. Issues are discussed, and conclusions and recommendations are provided.
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Patricia Rodriguez de Gil, University of South Florida
Shetay Ashford, University of South Florida
Chunhua Cao, University of South Florida
Eun-Sook Kim, University of South Florida
Rheta Lanehart, University of South Florida
Reginald Lee, University of South Florida
Jessica Montgomery, University of South Florida
Yan Wang, University of South Florida
Paper 3497-2015:
Analytics to Inform Name Your Own Price Reserve Setting
Behind an e-commerce site selling many thousands of live events, with inventory from thousands of ticket suppliers who can and do change prices constantly, and all the historical data on prices for this and similar events, layer in customer bidding behavior and you have a big data opportunity on your hands. I will talk about the evolution of pricing at ScoreBig in this framework and the models we've developed to set our reserve pricing. These models and the underlying data are also used by our inventory partners to continue to refine their pricing. I will also highlight how having a name your own price framework helps with the development of pricing models.
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Alison Burnham, ScoreBig Inc
Paper 3369-2015:
Analyzing Customer Answers in Calls from Collections Using SAS® Text Miner to Respond in an Efficient and Effective Way
At the Multibanca Colpatria of Scotiabank, we offer a broad range of financial services and products in Colombia. In collection management, we currently manage more than 400,000 customers each month. In the call center, agents collect answers from each contact with the customer, and this information is saved in databases. However, this information has not been explored to know more about our customers and our own operation. The objective of this paper is to develop a classification model using the words in the answers from each customer from the call about receiving payment. Using a combination of text mining and cluster methodologies, we identify the possible conversations that can occur in each stage of delinquency. This knowledge makes developing specialized scripts for collection management possible.
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Oscar Ayala, Colpatria
Jenny Lancheros, Banco Colpatria Of ScotiaBank Group
Paper 3293-2015:
Analyzing Direct Marketing Campaign Performance Using Weight of Evidence Coding and Information Value through SAS® Enterprise Miner™ Incremental Response
Data mining and predictive models are extensively used to find the optimal customer targets in order to maximize the return on investment. Direct marketing techniques target all the customers who are likely to buy regardless of the customer classification. In a real sense, this mechanism couldn't classify the customers who are going to buy even without a marketing contact, thereby resulting in a loss on investment. This paper focuses on the Incremental Lift modeling approach using Weight of Evidence Coding and Information Value followed by Incremental Response and Outcome model Diagnostics. This model identifies the additional purchases that would not have taken place without a marketing campaign. Modeling work was conducted using a combined model. The research work is carried out on Travel Center data. This data identifies the increase in average response rate by 2.8% and the number of fuel gallons by 244 when compared with the results from the traditional campaign, which targeted everyone. This paper discusses in detail the implementation of the 'Incremental Response' node to direct the marketing campaigns and its Incremental Revenue and Profit analysis.
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Sravan Vadigepalli, Best Buy
Paper 3472-2015:
Analyzing Marine Piracy from Structured and Unstructured Data Using SAS® Text Miner
Approximately 80% of world trade at present uses the seaways, with around 110,000 merchant vessels and 1.25 million marine farers transported and almost 6 billion tons of goods transferred every year. Marine piracy stands as a serious challenge to sea trade. Understanding how the pirate attacks occur is crucial in effectively countering marine piracy. Predictive modeling using the combination of textual data with numeric data provides an effective methodology to derive insights from both structured and unstructured data. 2,266 text descriptions about pirate incidents that occurred over the past seven years, from 2008 to the second quarter of 2014, were collected from the International Maritime Bureau (IMB) website. Analysis of the textual data using SAS® Enterprise Miner™ 12.3, with the help of concept links, answered questions on certain aspects of pirate activities, such as the following: 1. What are the arms used by pirates for attacks? 2. How do pirates steal the ships? 3. How do pirates escape after the attacks? 4. What are the reasons for occasional unsuccessful attacks? Topics are extracted from the text descriptions using a text topic node, and the varying trends of these topics are analyzed with respect to time. Using the cluster node, attack descriptions are classified into different categories based on attack style and pirate behavior described by a set of terms. A target variable called Attack Type is derived from the clusters and is combined with other structured input variables such as Ship Type, Status, Region, Part of Day, and Part of Year. A Predictive model is built with Attact Type as the target variable and other structured data variables as input predictors. The Predictive model is used to predict the possible type of attack given the details of the ship and its travel. Thus, the results of this paper could be very helpful for the shipping industry to become more aware of possible attack types for different vessel types when traversing different routes , and to devise counter-strategies in reducing the effects of piracy on crews, vessels, and cargo.
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Raghavender Reddy Byreddy, Oklahoma State University
Nitish Byri, Oklahoma State University
Goutam Chakraborty, Oklahoma State University
Tejeshwar Gurram, Oklahoma State University
Anvesh Reddy Minukuri, Oklahoma State University
Paper SAS2082-2015:
Analyzing Messy and Wide Data on a Desktop
Data comes from a rich variety of sources in a rich variety of types, shapes, sizes, and properties. The analysis can be challenged by data that is too tall or too wide; too full of miscodings, outliers, or holes; or that contains funny data types. Wide data, in particular, has many challenges, requiring the analysis to adapt with different methods. Making covariance matrices with 2.5 billion elements is just not practical. JMP® 12 will address these challenges.
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John Sall, SAS
Paper SAS1332-2015:
Analyzing Spatial Point Patterns Using the New SPP Procedure
In many spatial analysis applications (including crime analysis, epidemiology, ecology, and forestry), spatial point process modeling can help you study the interaction between different events and help you model the process intensity (the rate of event occurrence per unit area). For example, crime analysts might want to estimate where crimes are likely to occur in a city and whether they are associated with locations of public features such as bars and bus stops. Forestry researchers might want to estimate where trees grow best and test for association with covariates such as elevation and gradient. This paper describes the SPP procedure, new in SAS/STAT® 13.2, for exploring and modeling spatial point pattern data. It describes methods that PROC SPP implements for exploratory analysis of spatial point patterns and for log-linear intensity modeling that uses covariates. It also shows you how to use specialized functions for studying interactions between points and how to use specialized analytical graphics to diagnose log-linear models of spatial intensity. Crime analysis, forestry, and ecology examples demonstrate key features of PROC SPP.
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Pradeep Mohan, SAS
Randy Tobias, SAS
Paper 3330-2015:
Analyzing and Visualizing the Sentiment of the Ebola Outbreak via Tweets
The Ebola virus outbreak is producing some of the most significant and fastest trending news throughout the globe today. There is a lot of buzz surrounding the deadly disease and the drastic consequences that it potentially poses to mankind. Social media provides the basic platforms for millions of people to discuss the issue and allows them to openly voice their opinions. There has been a significant increase in the magnitude of responses all over the world since the death of an Ebola patient in a Dallas, Texas hospital. In this paper, we aim to analyze the overall sentiment that is prevailing in the world of social media. For this, we extracted the live streaming data from Twitter at two different times using the Python scripting language. One instance relates to the period before the death of the patient, and the other relates to the period after the death. We used SAS® Text Miner nodes to parse, filter, and analyze the data and to get a feel for the patterns that exist in the tweets. We then used SAS® Sentiment Analysis Studio to further analyze and predict the sentiment of the Ebola outbreak in the United States. In our results, we found that the issue was not taken very seriously until the death of the Ebola patient in Dallas. After the death, we found that prominent personalities across the globe were talking about the disease and then raised funds to fight it. We are continuing to collect tweets. We analyze the locations of the tweets to produce a heat map that corresponds to the intensity of the varying sentiment across locations.
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Dheeraj Jami, Oklahoma State University
Goutam Chakraborty, Oklahoma State University
Shivkanth Lanka, Oklahoma State University
Paper 3050-2015:
Automation of Statistics Summary for Census Data in SAS®
Census data, such as education and income, has been extensively used for various purposes. The data is usually collected in percentages of census unit levels, based on the population sample. Such presentation of the data makes it hard to interpret and compare. A more convenient way of presenting the data is to use the geocoded percentage to produce counts for a pseudo-population. We developed a very flexible SAS® macro to automatically generate the descriptive summary tables for the census data as well as to conduct statistical tests to compare the different levels of the variable by groups. The SAS macro is not only useful for census data but can be used to generate summary tables for any data with percentages in multiple categories.
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Janet Lee, Kaiser Permanente Southern California
C
Paper 2080-2015:
Calculate Decision Consistency Statistics for a Single Administration of a Test
Many certification programs classify candidates into performance levels. For example, the SAS® Certified Base Programmer breaks down candidates into two performance levels: Pass and Fail. It is important to note that because all test scores contain measurement error, the performance level categorizations based on those test scores are also subject to measurement error. An important part of psychometric analysis is to estimate the decision consistency of the classifications. This study helps fill a gap in estimating decision consistency statistics for a single administration of a test using SAS.
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Fan Yang, The University of Iowa
Yi Song, University of Illinois at Chicago
Paper 3148-2015:
Catering to Your Tastes: Using PROC OPTEX to Design Custom Experiments, with Applications in Food Science and Field Trials
The success of an experimental study almost always hinges on how you design it. Does it provide estimates for everything you're interested in? Does it take all the experimental constraints into account? Does it make efficient use of limited resources? The OPTEX procedure in SAS/QC® software enables you to focus on specifying your interests and constraints, and it takes responsibility for handling them efficiently. With PROC OPTEX, you skip the step of rifling through tables of standard designs to try to find the one that's right for you. You concentrate on the science and the analytics and let SAS® do the computing. This paper reviews the features of PROC OPTEX and shows them in action using examples from field trials and food science experimentation. PROC OPTEX is a useful tool for all these situations, doing the designing and freeing the scientist to think about the food and the biology.
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Cliff Pereira, Dept of Statistics, Oregon State University
Randy Tobias, SAS
Paper 2380-2015:
Chi-Square and T Tests Using SAS®: Performance and Interpretation
Data analysis begins with cleaning up data, calculating descriptive statistics, and examining variable distributions. Before more rigorous statistical analysis begins, many statisticians perform basic inferential statistical tests such as chi-square and t tests to assess unadjusted associations. These tests help guide the direction of the more rigorous statistical analysis. How to perform chi-square and t tests is presented. We explain how to interpret the output and where to look for the association or difference based on the hypothesis being tested. We propose the next steps for further analysis using example data.
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Maribeth Johnson, Georgia Regents University
Jennifer Waller, Georgia Regents University
Paper 3291-2015:
Coding Your Own MCMC Algorithm
In Bayesian statistics, Markov chain Monte Carlo (MCMC) algorithms are an essential tool for sampling from probability distributions. PROC MCMC is useful for these algorithms. However, it is often desirable to code an algorithm from scratch. This is especially present in academia where students are expected to be able to understand and code an MCMC. The ability of SAS® to accomplish this is relatively unknown yet quite straightforward. We use SAS/IML® to demonstrate methods for coding an MCMC algorithm with examples of a Gibbs sampler and Metropolis-Hastings random walk.
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Chelsea Lofland, University of California Santa Cruz
Paper 1424-2015:
Competing Risk Survival Analysis Using SAS®: When, Why, and How
Competing risk arise in time to event data when the event of interest cannot be observed because of a preceding event i.e. a competing event occurring before. An example can be of an event of interest being a specific cause of death where death from any other cause can be termed as a competing event, if focusing on relapse, death before relapse would constitute a competing event. It is well studied and pointed out that in presence of competing risks, the standard product limit methods yield biased results due to violation of their basic assumption. The effect of competing events on parameter estimation depends on their distribution and frequency. Fine and Gray's sub-distribution hazard model can be used in presence of competing events which is available in PROC PHREG with the release of version 9.4 of SAS® software.
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Lovedeep Gondara, University of Illinois Springfield
Paper 3249-2015:
Cutpoint Determination Methods in Survival Analysis Using SAS®: Updated %FINDCUT Macro
Statistical analysis that uses data from clinical or epidemiological studies include continuous variables such as patient's age, blood pressure, and various biomarkers. Over the years, there has been an increase in studies that focus on assessing associations between biomarkers and disease of interest. Many of the biomarkers are measured as continuous variables. Investigators seek to identify the possible cutpoint to classify patients as high risk versus low risk based on the value of the biomarker. Several data-oriented techniques such as median and upper quartile, and outcome-oriented techniques based on score, Wald, and likelihood ratio tests are commonly used in the literature. Contal and O'Quigley (1999) presented a technique that used log rank test statistic in order to estimate the cutpoint. Their method was computationally intensive and hence was overlooked due to the unavailability of built-in options in standard statistical software. In 2003, we provided the %FINDCUT macro that used Contal and O'Quigley's approach to identify a cutpoint when the outcome of interest was measured as time to event. Over the past decade, demand for this macro has continued to grow, which has led us to consider updating the %FINDCUT macro to incorporate new tools and procedures from SAS® such as array processing, Graph Template Language, and the REPORT procedure. New and updated features include: results presented in a much cleaner report format, user-specified cutpoints, macro parameter error checking, temporary data set cleanup, preserving current option settings, and increased processing speed. We present the utility and added options of the revised %FINDCUT macro using a real-life data set. In addition, we critically compare this method to some of the existing methods and discuss the use and misuse of categorizing a continuous covariate.
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Jay Mandrekar, Mayo Clinic
Jeffrey Meyers, Mayo Clinic
D
Paper SAS4780-2015:
Deriving Insight Across the Enterprise from Digital Data
Learn how leading retailers are developing key findings in digital data to be leveraged across marketing, merchandising, and IT.
Rachel Thompson, SAS
Paper 3021-2015:
Discovering Personality Type through Text Mining in SAS® Enterprise Miner™ 12.3
Data scientists and analytic practitioners have become obsessed with quantifying the unknown. Through text mining third-person posthumous narratives in SAS® Enterprise Miner™ 12.1, we measured tangible aspects of personalities based on the broadly accepted big-five characteristics: extraversion, agreeableness, conscientiousness, neuroticism, and openness. These measurable attributes are linked to common descriptive terms used throughout our data to establish statistical relationships. The data set contains over 1,000 obituaries from newspapers throughout the United States, with individuals who vary in age, gender, demographic, and socio-economic circumstances. In our study, we leveraged existing literature to build the ontology used in the analysis. This literature suggests that a third person's perspective gives insight into one's personality, solidifying the use of obituaries as a source for analysis. We statistically linked target topics such as career, education, religion, art, and family to the five characteristics. With these taxonomies, we developed multivariate models in order to assign scores to predict an individual's personality type. With a trained model, this study has implications for predicting an individual's personality, allowing for better decisions on human capital deployment. Even outside the traditional application of personality assessment for organizational behavior, the methods used to extract intangible characteristics from text enables us to identify valuable information across multiple industries and disciplines.
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Mark Schneider, Deloitte & Touche
Andrew Van Der Werff, Deloitte & Touche, LLP
Paper 2442-2015:
Don't Copy and Paste--Use BY Statement Processing with ODS to Make Your Summary Tables
Most manuscripts in medical journals contain summary tables that combine simple summaries and between-group comparisons. These tables typically combine estimates for categorical and continuous variables. The statistician generally summarizes the data using the FREQ procedure for categorical variables and compares percentages between groups using a chi-square or a Fisher's exact test. For continuous variables, the MEANS procedure is used to summarize data as either means and standard deviation or medians and quartiles. Then these statistics are generally compared between groups by using the GLM procedure or NPAR1WAY procedure, depending on whether one is interested in a parametric test or a non-parametric test. The outputs from these different procedures are then combined and presented in a concise format ready for publications. Currently there is no straightforward way in SAS® to build these tables in a presentable format that can then be customized to individual tastes. In this paper, we focus on presenting summary statistics and results from comparing categorical variables between two or more independent groups. The macro takes the dataset, the number of treatment groups, and the type of test (either chi-square or Fisher's exact) as input and presents the results in a publication-ready table. This macro automates summarizing data to a certain extent and minimizes risky typographical errors when copying results or typing them into a table.
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Jeff Gossett, University of Arkansas for Medical Sciences
Mallikarjuna Rettiganti, UAMS
Paper 3347-2015:
Donor Sentiment and Characteristic Analysis Using SAS® Enterprise Miner™ and SAS® Sentiment Analysis Studio
It has always been a million-dollar question, What inhibits a donor to donate? Many successful universities have deep roots in annual giving. We know donor sentiment is a key factor in drawing attention to engage donors. This paper is a summary of findings about donor behaviors using textual analysis combined with the power of predictive modeling. In addition to identifying the characteristics of donors, the paper focuses on identifying the characteristics of a first-time donor. It distinguishes the features of the first-time donor from the general donor pattern. It leverages the variations in data to provide deeper insights into behavioral patterns. A data set containing 247,000 records was obtained from the XYZ University Foundation alumni database, Facebook, and Twitter. Solicitation content such as email subject lines sent to the prospect base was considered. Time-dependent data and time-independent data were categorized to make unbiased predictions about the first-time donor. The predictive models use input such as age, educational records, scholarships, events, student memberships, and solicitation methods. Models such as decision trees, Dmine regression, and neural networks were built to predict the prospects. SAS® Sentiment Analysis Studio and SAS® Enterprise Miner™ were used to analyze the sentiment.
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Ramcharan Kakarla, Comcast
Goutam Chakraborty, Oklahoma State University
Paper 3381-2015:
Double Generalized Linear Models Using SAS®: The %DOUBLEGLM Macro
The purpose of this paper is to introduce a SAS® macro named %DOUBLEGLM that enables users to model the mean and dispersion jointly using double generalized linear models described in Nelder (1991) and Lee (1998). The R functions FITJOINT and DGLM (R Development Core Team, 2011) were used to verify the suitability of the %DOUBLEGLM macro estimates. The results showed that estimates were closer than the R functions.
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Paulo Silva, Universidade de Brasilia
Alan Silva, Universidade de Brasilia
Paper SAS1865-2015:
Drilling for Deepwater Data: A Forensic Analysis of the Gulf of Mexico Deepwater Horizon Disaster
During the cementing and pumps-off phase of oil drilling, drilling operations need to know, in real time, about any loss of hydrostatic or mechanical well integrity. This phase involves not only big data, but also high-velocity data. Today's state-of-the-art drilling rigs have tens of thousands of sensors. These sensors and their data output must be correlated and analyzed in real time. This paper shows you how to leverage SAS® Asset Performance Analytics and SAS® Enterprise Miner™ to build a model for drilling and well control anomalies, fingerprint key well control measures of the transienct fluid properties, and how to operationalize these analytics on the drilling assets with SAS® event stream processing. We cover the implementation and results from the Deepwater Horizon case study, demonstrating how SAS analytics enables the rapid differentiation between safe and unsafe modes of operation.
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Jim Duarte, SAS
Keith Holdaway, SAS
Moray Laing, SAS
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Paper 3083-2015:
Easing into Analytics Using SAS® Enterprise Guide® 6.1
Do you need to deliver business insight and analytics to support decision-making? Using SAS® Enterprise Guide®, you can access the full power of SAS® for analytics, without needing to learn the details of SAS programming. This presentation focuses on the following uses of SAS Enterprise Guide: Exploring and understanding--getting a feel for your data and for its issues and anomalies Visualizing--looking at the relationships, trends, surprises Consolidating--starting to piece together the story Presenting--building the insight and analytics into a presentation using SAS Enterprise Guide
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Marje Fecht, Prowerk Consulting
Paper 3329-2015:
Efficiently Using SAS® Data Views
For the Research Data Centers (RDCs) of the United States Census Bureau, the demand for disk space substantially increases with each passing year. Efficiently using the SAS® data view might successfully address the concern about disk space challenges within the RDCs. This paper discusses the usage and benefits of the SAS data view to save disk space and reduce the time and effort required to manage large data sets. The ability and efficiency of the SAS data view to process regular ASCII, compressed ASCII, and other commonly used file formats are analyzed and evaluated in detail. The authors discuss ways in which using SAS data views is more efficient than the traditional methods in processing and deploying the large census and survey data in the RDCs.
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Shigui Weng, US Bureau of the Census
Shy Degrace, US BUREAU OF THE CENSUS
Ya Jiun Tsai, US BUREAU OF THE CENSUS
Paper SAS1775-2015:
Encore: Introduction to Bayesian Analysis Using SAS/STAT®
The use of Bayesian methods has become increasingly popular in modern statistical analysis, with applications in numerous scientific fields. In recent releases, SAS® software has provided a wealth of tools for Bayesian analysis, with convenient access through several popular procedures in addition to the MCMC procedure, which is designed for general Bayesian modeling. This paper introduces the principles of Bayesian inference and reviews the steps in a Bayesian analysis. It then uses examples from the GENMOD and PHREG procedures to describe the built-in Bayesian capabilities, which became available for all platforms in SAS/STAT® 9.3. Discussion includes how to specify prior distributions, evaluate convergence diagnostics, and interpret the posterior summary statistics.
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Maura Stokes, SAS
Paper 3920-2015:
Entity Resolution and Master Data Life Cycle Management in the Era of Big Data
Proper management of master data is a critical component of any enterprise information system. However, effective master data management (MDM) requires that both IT and Business understand the life cycle of master data and the fundamental principles of entity resolution (ER). This presentation provides a high-level overview of current practices in data matching, record linking, and entity information life cycle management that are foundational to building an effective strategy to improve data integration and MDM. Particular areas of focus are: 1) The need for ongoing ER analytics--the systematic and quantitative measurement of ER performance; 2) Investing in clerical review and asserted resolution for continuous improvement; and 3) Addressing the large-scale ER challenge through distributed processing.
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John Talburt, Black Oak Analytics, Inc
Paper 3242-2015:
Entropy-Based Measures of Weight of Evidence and Information Value for Variable Reduction and Segmentation for Continuous Dependent Variables
My SAS® Global Forum 2013 paper 'Variable Reduction in SAS® by Using Weight of Evidence (WOE) and Information Value (IV)' has become the most sought-after online article on variable reduction in SAS since its publication. But the methodology provided by the paper is limited to reduction of numeric variables for logistic regression only. Built on a similar process, the current paper adds several major enhancements: 1) The use of WOE and IV has been expanded to the analytics and modeling for continuous dependent variables. After the standardization of a continuous outcome, all records can be divided into two groups: positive performance (outcome y above sample average) and negative performance (outcome y below sample average). This treatment is rigorously consistent with the concept of entropy in Information Theory: the juxtaposition of two opposite forces in one equation, and a stronger contrast between the two suggests a higher intensity , that is, more information delivered by the variable in question. As the standardization keeps the outcome variable continuous and quantified, the revised formulas for WOE and IV can be used in the analytics and modeling for continuous outcomes such as sales volume, claim amount, and so on. 2) Categorical and ordinal variables can be assessed together with numeric ones. 3) Users of big data usually need to evaluate hundreds or thousands of variables, but it is not uncommon that over 90% of variables contain little useful information. We have added a SAS macro that trims these variables efficiently in a broad-brushed manner without a thorough examination. Afterward, we examine the retained variables more carefully on their behaviors to the target outcome. 4) We add Chi-Square analysis for categorical/ordinal variables and Gini coefficients for numeric variable in order to provide additional suggestions for segmentation and regression. With the above enhancements added, a SAS macro program is provided at the end of the paper as a complete suite for variable reduction/selection that efficiently evaluates all variables together. The paper provides a detailed explanation for how to use the SAS macro and how to read the SAS outputs that provide useful insights for subsequent linear regression, logistic regression, or scorecard development.
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Alec Zhixiao Lin, PayPal Credit
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Paper 3419-2015:
Forest Plotting Analysis Macro %FORESTPLOT
A powerful tool for visually analyzing regression analysis is the forest plot. Model estimates, ratios, and rates with confidence limits are graphically stacked vertically in order to show how they overlap with each other and to show values of significance. The ability to see whether two values are significantly different from each other or whether a covariate has a significant meaning on its own is made much simpler in a forest plot rather than sifting through numbers in a report table. The amount of data preparation needed in order to build a high-quality forest plot in SAS® can be tremendous because the programmer needs to run analyses, extract the estimates to be plotted, structure the estimates in a format conducive to generating a forest plot, and then run the correct plotting procedure or create a graph template using the Graph Template Language (GTL). While some SAS procedures can produce forest plots using Output Delivery System (ODS) Graphics automatically, the plots are not generally publication-ready and are difficult to customize even if the programmer is familiar with GTL. The macro %FORESTPLOT is designed to perform all of the steps of building a high-quality forest plot in order to save time for both experienced and inexperienced programmers, and is currently set up to perform regression analyses common to the clinical oncology research areas, Cox proportional hazards and logistic, as well as calculate Kaplan-Meier event-free rates. To improve flexibility, the user can specify a pre-built data set to transform into a forest plot if the automated analysis options of the macro do not fit the user's needs.
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Jeffrey Meyers, Mayo Clinic
Qian Shi, Mayo Clinic
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Paper SAS4121-2015:
Getting Started with Logistic Regression in SAS
This presentation provides a brief introduction to logistic regression analysis in SAS. Learn differences between Linear Regression and Logistic Regression, including ordinary least squares versus maximum likelihood estimation. Learn to: understand LOGISTIC procedure syntax, use continuous and categorical predictors, and interpret output from ODS Graphics.
Danny Modlin, SAS
Paper SAS4140-2015:
Getting Started with Mixed Models in Business
For decades, mixed models been used by researchers to account for random sources of variation in regression-type models. Now they are gaining favor in business statistics to give better predictions for naturally occurring groups of data, such as sales reps, store locations, or regions. Learn about how predictions based on a mixed model differ from predictions in ordinary regression, and see examples of mixed models with business data.
Catherine Truxillo, SAS
Paper SAS4122-2015:
Getting Started with SAS ® Contextual Analysis: Easily build models from unstructured data
Text data constitutes more than half of the unstructured data held in organizations. Buried within the narrative of customer inquiries, the pages of research reports, and the notes in servicing transactions are the details that describe concerns, ideas and opportunities. The historical manual effort needed to develop a training corpus is now no longer required, making it simpler to gain insight buried in unstructured text. With the ease of machine learning refined with the specificity of linguistic rules, SAS Contextual Analysis helps analysts identify and evaluate the meaning of the electronic written word. From a single, point-and-click GUI interface the process of developing text models is guided and visually intuitive. This presentation will walk through the text model development process with SAS Contextual Analysis. The results are in SAS format, ready for text-based insights to be used in any other SAS application.
George Fernandez, SAS
Paper SAS4123-2015:
Getting Started with Time Series Data and Forecasting in SAS
SAS/ETS provides many tools to improve the productivity of the analyst who works with time series data. This tutorial will take an analyst through the process of turning transaction-level data into a time series. The session will then cover some basic forecasting techniques that use past fluctuations to predict future events. We will then extend this modeling technique to include explanatory factors in the prediction equation.
Kenneth Sanford, SAS
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Paper SAS1708-2015:
How SAS® Uses SAS to Analyze SAS Blogs
SAS® blogs (hosted at http://blogs.sas.com/content) attract millions of page views annually. With hundreds of authors, thousands of posts, and constant chatter within the blog comments, it's impossible for one person to keep track of all of the activity. In this paper, you learn how SAS technology is used to gather data and report on SAS blogs from the inside out. The beneficiaries include personnel from all over the company, including marketing, technical support, customer loyalty, and executives. The author describes the business case for tracking and reporting on the activity of blogging. You learn how SAS tools are used to access the WordPress database and how to create a 'blog data mart' for reporting and analytics. The paper includes specific examples of the insight that you can gain from examining the blogs analytically, and which techniques are most useful for achieving that insight. For example, the blog transactional data are combined with social media metrics (also gathered by using SAS) to show which blog entries and authors yield the most engagement on Twitter, Facebook, and LinkedIn. In another example, we identified the growing trend of 'blog comment spam' on the SAS blog properties and measured its cost to the business. These metrics helped to justify the investment in a solution. Many of the tools used are part of SAS® Foundation, including SAS/ACCESS®, the DATA step and SQL, PROC REPORT, PROC SGPLOT, and more. The results are shared in static reports, automated daily email summaries, dynamic reports hosted in SAS/IntrNet®, and even a corporate dashboard hosted in SAS® Visual Analytics.
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Chris Hemedinger, SAS
Paper 3185-2015:
How to Hunt for Utility Customer Electric Usage Patterns Armed with SAS® Visual Statistics with Hadoop and Hive
Your electricity usage patterns reveal a lot about your family and routines. Information collected from electrical smart meters can be mined to identify patterns of behavior that can in turn be used to help change customer behavior for the purpose of altering system load profiles. Demand Response (DR) programs represent an effective way to cope with rising energy needs and increasing electricity costs. The Federal Energy Regulatory Commission (FERC) defines demand response as changes in electric usage by end-use customers from their normal consumption patterns in response to changes in the price of electricity over time, or to incentive payments designed to lower electricity use at times of high wholesale market prices or when system reliability of jeopardized. In order to effectively motivate customers to voluntarily change their consumptions patterns, it is important to identify customers whose load profiles are similar so that targeted incentives can be directed toward these customers. Hence, it is critical to use tools that can accurately cluster similar time series patterns while providing a means to profile these clusters. In order to solve this problem, though, hardware and software that is capable of storing, extracting, transforming, loading and analyzing large amounts of data must first be in place. Utilities receive customer data from smart meters, which track and store customer energy usage. The data collected is sent to the energy companies every fifteen minutes or hourly. With millions of meters deployed, this quantity of information creates a data deluge for utilities, because each customer generates about three thousand data points monthly, and more than thirty-six billion reads are collected annually for a million customers. The data scientist is the hunter, and DR candidate patterns are the prey in this cat-and-mouse game of finding customers willing to curtail electrical usage for a program benefit. The data scientist must connect large siloed data sources, external data , and even unstructured data to detect common customer electrical usage patterns, build dependency models, and score them against their customer population. Taking advantage of Hadoop's ability to store and process data on commodity hardware with distributed parallel processing is a game changer. With Hadoop, no data set is too large, and SAS® Visual Statistics leverages machine learning, artificial intelligence, and clustering techniques to build descriptive and predictive models. All data can be usable from disparate systems, including structured, unstructured, and log files. The data scientist can use Hadoop to ingest all available data at rest, and analyze customer usage patterns, system electrical flow data, and external data such as weather. This paper will use Cloudera Hadoop with Apache Hive queries for analysis on platforms such as SAS® Visual Analytics and SAS Visual Statistics. The paper will showcase optionality within Hadoop for querying large data sets with open-source tools and importing these data into SAS® for robust customer analytics, clustering customers by usage profiles, propensity to respond to a demand response event, and an electrical system analysis for Demand Response events.
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Kathy Ball, SAS
Paper 3252-2015:
How to Use SAS® for GMM Logistic Regression Models for Longitudinal Data with Time-Dependent Covariates
In longitudinal data, it is important to account for the correlation due to repeated measures and time-dependent covariates. Generalized method of moments can be used to estimate the coefficients in longitudinal data, although there are currently limited procedures in SAS® to produce GMM estimates for correlated data. In a recent paper, Lalonde, Wilson, and Yin provided a GMM model for estimating the coefficients in this type of data. SAS PROC IML was used to generate equations that needed to be solved to determine which estimating equations to use. In addition, this study extended classifications of moment conditions to include a type IV covariate. Two data sets were evaluated using this method, including re-hospitalization rates from a Medicare database as well as body mass index and future morbidity rates among Filipino children. Both examples contain binary responses, repeated measures, and time-dependent covariates. However, while this technique is useful, it is tedious and can also be complicated when determining the matrices necessary to obtain the estimating equations. We provide a concise and user-friendly macro to fit GMM logistic regression models with extended classifications.
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Katherine Cai, Arizona State University
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Paper 3411-2015:
Identifying Factors Associated with High-Cost Patients
Research has shown that the top five percent of patients can account for nearly fifty percent of the total healthcare expenditure in the United States. Using SAS® Enterprise Guide® and PROC LOGISTIC, a statistical methodology was developed to identify factors (for example, patient demographics, diagnostic symptoms, comorbidity, and the type of procedure code) associated with the high cost of healthcare. Analyses were performed using the FAIR Health National Private Insurance Claims (NPIC) database, which contains information about healthcare utilization and cost in the United States. The analyses focused on treatments for chronic conditions, such as trans-myocardial laser revascularization for the treatment of coronary heart disease (CHD) and pressurized inhalation for the treatment of asthma. Furthermore, bubble plots and heat maps were created using SAS® Visual Analytics to provide key insights into potentially high-cost treatments for heart disease and asthma patients across the nation.
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Jeff Dang, FAIR Health
Paper 3295-2015:
Imputing Missing Data using SAS®
Missing data is an unfortunate reality of statistics. However, there are various ways to estimate and deal with missing data. This paper explores the pros and cons of traditional imputation methods versus maximum likelihood estimation as well as singular versus multiple imputation. These differences are displayed through comparing parameter estimates of a known data set and simulating random missing data of different severity. In addition, this paper uses PROC MI and PROC MIANALYZE and shows how to use these procedures in a longitudinal data set.
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Christopher Yim, Cal Poly San Luis Obispo
Paper 3052-2015:
Introduce a Linear Regression Model by Using the Variable Transformation Method
This paper explains how to build a linear regression model using the variable transformation method. Testing the assumptions, which is required for linear modeling and testing the fit of a linear model, is included. This paper is intended for analysts who have limited exposure to building linear models. This paper uses the REG, GLM, CORR, UNIVARIATE, and GPLOT procedures.
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Nancy Hu, Discover
Paper SAS1742-2015:
Introducing the HPGENSELECT Procedure: Model Selection for Generalized Linear Models and More
Generalized linear models are highly useful statistical tools in a broad array of business applications and scientific fields. How can you select a good model when numerous models that have different regression effects are possible? The HPGENSELECT procedure, which was introduced in SAS/STAT® 12.3, provides forward, backward, and stepwise model selection for generalized linear models. In SAS/STAT 14.1, the HPGENSELECT procedure also provides the LASSO method for model selection. You can specify common distributions in the family of generalized linear models, such as the Poisson, binomial, and multinomial distributions. You can also specify the Tweedie distribution, which is important in ratemaking by the insurance industry and in scientific applications. You can run the HPGENSELECT procedure in single-machine mode on the server where SAS/STAT is installed. With a separate license for SAS® High-Performance Statistics, you can also run the procedure in distributed mode on a cluster of machines that distribute the data and the computations. This paper shows you how to use the HPGENSELECT procedure both for model selection and for fitting a single model. The paper also explains the differences between the HPGENSELECT procedure and the GENMOD procedure.
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Gordon Johnston, SAS
Bob Rodriguez, SAS
Paper 2986-2015:
Introduction to Output Delivery System (ODS)
This presentation teaches the audience how to use ODS Graphics. Now part of Base SAS®, ODS Graphics are a great way to easily create clear graphics that enable any user to tell their story well. SGPLOT and SGPANEL are two of the procedures that can be used to produce powerful graphics that used to require a lot of work. The core of the procedures is explained, as well as some of the many options available. Furthermore, we explore the ways to combine the individual statements to make more complex graphics that tell the story better. Any user of Base SAS on any platform will find great value in the SAS ODS Graphics procedures.
Chuck Kincaid, Experis
J
Paper 3020-2015:
Jeffreys Interval for One-Sample Proportion with SAS/STAT® Software
This paper introduces Jeffreys interval for one-sample proportion using SAS® software. It compares the credible interval from a Bayesian approach with the confidence interval from a frequentist approach. Different ways to calculate the Jeffreys interval are presented using PROC FREQ, the QUANTILE function, a SAS program of the random walk Metropolis sampler, and PROC MCMC.
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Wu Gong, The Children's Hospital of Philadelphia
K
Paper 2480-2015:
Kaplan-Meier Survival Plotting Macro %NEWSURV
The research areas of pharmaceuticals and oncology clinical trials greatly depend on time-to-event endpoints such as overall survival and progression-free survival. One of the best graphical displays of these analyses is the Kaplan-Meier curve, which can be simple to generate with the LIFETEST procedure but difficult to customize. Journal articles generally prefer that statistics such as median time-to-event, number of patients, and time-point event-free rate estimates be displayed within the graphic itself, and this was previously difficult to do without an external program such as Microsoft Excel. The macro %NEWSURV takes advantage of the Graph Template Language (GTL) that was added with the SG graphics engine to create this level of customizability without the need for back-end manipulation. Taking this one step further, the macro was improved to be able to generate a lattice of multiple unique Kaplan-Meier curves for side-by-side comparisons or for condensing figures for publications. This paper describes the functionality of the macro and describes how the key elements of the macro work.
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Jeffrey Meyers, Mayo Clinic
L
Paper 3297-2015:
Lasso Regularization for Generalized Linear Models in Base SAS® Using Cyclical Coordinate Descent
The cyclical coordinate descent method is a simple algorithm that has been used for fitting generalized linear models with lasso penalties by Friedman et al. (2007). The coordinate descent algorithm can be implemented in Base SAS® to perform efficient variable selection and shrinkage for GLMs with the L1 penalty (the lasso).
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Robert Feyerharm, Beacon Health Options
Paper SPON2000-2015:
Leveraging In-Database Technology to Enhance Data Governance and Improve Performance
In-database processing refers to the integration of advanced analytics into the data warehouse. With this capability, analytic processing is optimized to run where the data reside, in parallel, without having to copy or move the data for analysis. From a data governance perspective there are many good reasons to embrace in-database processing. Many analytical computing solutions and large databases use this technology because it provides significant performance improvements over more traditional methods. Come learn how Blue Cross Blue Shield of Tennessee (BCBST) uses in-database processing from SAS and Teradata.
Harold Klagstad, BlueCross BlueShield of TN
Paper 3342-2015:
Location-Based Association of Customer Sentiment and Retail Sales
There are various economic factors that affect retail sales. One important factor that is expected to correlate is overall customer sentiment toward a brand. In this paper, we analyze how location-specific customer sentiment could vary and correlate with sales at retail stores. In our attempt to find any dependency, we have used location-specific Twitter feeds related to a national-brand chain retail store. We opinion-mine their overall sentiment using SAS® Sentiment Analysis Studio. We estimate correlation between the opinion index and retail sales within the studied geographic areas. Later in the analysis, using ArcGIS Online from Esri, we estimate whether other location-specific variables that could potentially correlate with customer sentiment toward the brand are significantly important to predict a brand's retail sales.
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Asish Satpathy, University of California, Riverside
Goutam Chakraborty, Oklahoma State University
Tanvi Kode, Oklahoma State University
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Paper 2481-2015:
Managing Extended Attributes With a SAS® Enterprise Guide® Add-In
SAS® 9.4 introduced extended attributes, which are name-value pairs that can be attached to either the data set or to individual variables. Extended attributes are managed through PROC DATASETS and can be viewed through PROC CONTENTS or through Dictionary.XATTRS. This paper describes the development of a SAS® Enterprise Guide® custom add-in that allows for the entry and editing of extended attributes, with the possibility of using a controlled vocabulary. The controlled vocabulary used in the initial application is derived from the lifecycle branch of the Data Documentation Initiative metadata standard (DDI-L).
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Larry Hoyle, IPSR, Univ. of Kansas
Paper 3193-2015:
Mapping out SG Procedures and Using PROC SGPLOT for Mapping
This paper describes the main functions of the SAS® SG procedures and their relations. It also offers a way to create data-colored maps using these procedures. Here are the basics of the SG procedures. For a few years, the SG procedures (PROC SGPLOT, PROC SGSCATTER, PROC SGPANEL, and so on) have been part of Base SAS® and thus available for everybody. SG originated as Statistical Graphics , but nowadays the procedures are often referred to as SAS® ODS Graphics. With the syntax in a 1000+ page document, it is quite a challenge to start using them. Also, SAS® Enterprise Guide® currently has no graphics tasks that generate code for the SG procedures (except those in the statistical arena). For a long time SAS/GRAPH® has been the vehicle for producing presentation-ready graphs of your data. In particular, the SAS users that have experience with those SAS/GRAPH procedures will hesitate to change over. But the SG procedures continue to be enhanced with new features. And, because the appearance of many elements is governed by the ODS styles, they are very well suited to provide a consistent style across all your output, text and graphics. PROC SGPLOT - PROC SGPANEL - PROC SGSCATTER: The paper first describes the basic procedures that a user will start with; PROC SGPLOT is the first place. Then the more elaborate possibilities of PROC SGPANEL and PROC SGSCATTER are described. Both these procedures can create a matrix or panel of graphs. The different goals of these two procedures will be explained: comparing a group of variables versus comparing the levels of two variables. PROC SGPLOT can create many different graphs: histograms, time series, scatterplots, and so on. PROC SGPANEL has essentially the same possibilities. The nature of PROC SGSCATTER (and the name says it already) limits it to scatter-like graphs. But many statements and options are common to lots of types of graphs. This paper groups them logically , making clear what the procedures have in common and where they differ. Related to the SG procedures are also two utilities (the Graphics Editor and the Graphics Designer), which are delivered as SAS® Foundation applications. The paper describes the relations between these utilities and the objects they produce, and the relevant SG procedures and related utilities. Creating a map for virtually all tasks that can be performed with the well known SAS/GRAPH procedures, the counterpart in the SG procedures is easily pointed out, often with more extensive features. This is not the case for the maps produced with PROC GMAP. This paper shows the mere few steps that are necessary to convert the data sets that contain your data and your map coordinates into data sets that enable you to use the power and features of PROC SGPLOT to create your map in any projection system and any coordinate window.
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Frank Poppe, PW Consulting
Paper SAS1822-2015:
Master Data and Command Results: Combine Master Data Management with SAS® Analytics for Improved Insights
It's well known that SAS® is the leader in advanced analytics but often overlooked is the intelligent data preparation that combines information from disparate sources to enable confident creation and deployment of compelling models. Improving data-based decision making is among the top reasons why organizations decide to embark on master data management (MDM) projects and why you should consider incorporating MDM functionality into your analytics-based processes. MDM is a discipline that includes the people, processes, and technologies for creating an authoritative view of core data elements in enterprise operational and analytic systems. This paper demonstrates why MDM functionality is a natural fit for many SAS solutions that need to have access to timely, clean, and unique master data. Because MDM shares many of the same technologies that power SAS analytic solutions, it has never been easier to add MDM capabilities to your advanced analytics projects.
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Ron Agresta, SAS
Paper 3375-2015:
Maximizing a Churn Campaign's Profitability with Cost-sensitive Predictive Analytics
Predictive analytics has been widely studied in recent years, and it has been applied to solve a wide range of real-world problems. Nevertheless, current state-of-the-art predictive analytics models are not well aligned with managers' requirements in that the models fail to include the real financial costs and benefits during the training and evaluation phases. Churn predictive modeling is one of those examples in which evaluating a model based on a traditional measure such as accuracy or predictive power does not yield the best results when measured by investment per subscriber in a loyalty campaign and the financial impact of failing to detect a real churner versus wrongly predicting a non-churner as a churner. In this paper, we propose a new financially based measure for evaluating the effectiveness of a voluntary churn campaign, taking into account the available portfolio of offers, their individual financial cost, and the probability of acceptance depending on the customer profile. Then, using a real-world churn data set, we compared different cost-insensitive and cost-sensitive predictive analytics models and measured their effectiveness based on their predictive power and cost optimization. The results show that using a cost-sensitive approach yields to an increase in profitability of up to 32.5%.
Alejandro Correa Bahnsen, University of Luxembourg
Darwin Amezquita, DIRECTV
Juan Camilo Arias, Smartics
Paper 2524-2015:
Methodology of Model Creation
The goal of this session is to describe the whole process of model creation from the business request through model specification, data preparation, iterative model creation, model tuning, implementation, and model servicing. Each mentioned phase consists of several steps in which we describe the main goal of the step, the expected outcome, the tools used, our own SAS codes, useful nodes, and settings in SAS® Enterprise Miner™, procedures in SAS® Enterprise Guide®, measurement criteria, and expected duration in man-days. For three steps, we also present deep insights with examples of practical usage, explanations of used codes, settings, and ways of exploring and interpreting the output. During the actual model creation process, we suggest using Microsoft Excel to keep all input metadata along with information about transformations performed in SAS Enterprise Miner. To get faster information about model results, we combine an automatic SAS® code generator implemented in Excel, and then we input this code to SAS Enterprise Guide and create a specific profile of results directly from the nodes output tables of SAS Enterprise Miner. This paper also focuses on an example of a binary model stability check-in time performed in SAS Enterprise Guide through measuring optimal cut-off percentage and lift. These measurements are visualized and automatized using our own codes. By using this methodology, users would have direct contact with transformed data along with the possibility to analyze and explore any semi-results. Furthermore, the proposed approach could be used for several types of modeling (for example, binary and nominal predictive models or segmentation models). Generally, we have summarized our best practices of combining specific procedures performed in SAS Enterprise Guide, SAS Enterprise Miner, and Microsoft Excel to create and interpret models faster and more effectively.
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Peter Kertys, VÚB a.s.
Paper 2400-2015:
Modeling Effect Modification and Higher-Order Interactions: A Novel Approach for Repeated Measures Design Using the LSMESTIMATE Statement in SAS® 9.4
Effect modification occurs when the association between a predictor of interest and the outcome is differential across levels of a third variable--the modifier. Effect modification is statistically tested as the interaction effect between the predictor and the modifier. In repeated measures studies (with more than two time points), higher-order (three-way) interactions must be considered to test effect modification by adding time to the interaction terms. Custom fitting and constructing these repeated measures models are difficult and time consuming, especially with respect to estimating post-fitting contrasts. With the advancement of the LSMESTIMATE statement in SAS®, a simplified approach can be used to custom test for higher-order interactions with post-fitting contrasts within a mixed model framework. This paper provides a simulated example with tips and techniques for using an application of the nonpositional syntax of the LSMESTIMATE statement to test effect modification in repeated measures studies. This approach, which is applicable to exploring modifiers in randomized controlled trials (RCTs), goes beyond the treatment effect on outcome to a more functional understanding of the factors that can enhance, reduce, or change this relationship. Using this technique, we can easily identify differential changes for specific subgroups of individuals or patients that subsequently impact treatment decision making. We provide examples of conventional approaches to higher-order interaction and post-fitting tests using the ESTIMATE statement and compare and contrast this to the nonpositional syntax of the LSMESTIMATE statement. The merits and limitations of this approach are discussed.
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Pronabesh DasMahapatra, PatientsLikeMe Inc.
Ryan Black, NOVA Southeastern University
Paper 3359-2015:
Modelling Operational Risk Using Extreme Value Theory and Skew t-Copulas via Bayesian Inference Using SAS®
Operational risk losses are heavy tailed and likely to be asymmetric and extremely dependent among business lines and event types. We propose a new methodology to assess, in a multivariate way, the asymmetry and extreme dependence between severity distributions and to calculate the capital for operational risk. This methodology simultaneously uses several parametric distributions and an alternative mix distribution (the lognormal for the body of losses and the generalized Pareto distribution for the tail) via the extreme value theory using SAS®; the multivariate skew t-copula applied for the first time to operational losses; and the Bayesian inference theory to estimate new n-dimensional skew t-copula models via Markov chain Monte Carlo (MCMC) simulation. This paper analyzes a new operational loss data set, SAS® Operational Risk Global Data (SAS OpRisk Global Data), to model operational risk at international financial institutions. All of the severity models are constructed in SAS® 9.2. We implement PROC SEVERITY and PROC NLMIXED and this paper describes this implementation.
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Betty Johanna Garzon Rozo, The University of Edinburgh
Paper 2720-2015:
Multinomial Logistic Model for Long-Term Value
Customer Long-Term Value (LTV) is a concept that is readily explained at a high level to marketing management of a company, but its analytic development is complex. This complexity involves the need to forecast customer behavior well into the future. This behavior includes the timing, frequency, and profitability of a customer's future purchases of products and services. This paper describes a method for computing LTV. First, a multinomial logistic regression provides probabilities for time-of-first-purchase, time-of-second-purchase, and so on, for each customer. Then the profits for the first purchase, second purchase, and so on, are forecast but only after adjustment for non-purchaser selection bias. Finally, these component models are combined in the LTV formula.
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Bruce Lund, Marketing Associates, LLC
Paper 3264-2015:
Multiple Product Affinity Makes Much More Sense
Retailers proactively seek a data-driven approach to provide customized product recommendations to guarantee sales increase and customer loyalty. Product affinity models have been recognized as one of the vital tools for this purpose. The algorithm assigns a customer to a product affinity group when the likelihood of purchasing is the highest and the likelihood meets the minimum and absolute requirement. However, in practice, valuable customers, up to 30% of the total universe, who buy across multiple product categories with two or more balanced product affinity likelihoods, are undefined and unable to be effectively product recommended. This paper presents multiple product affinity models that are developed using SAS® macro language to address the problem. In this paper, we demonstrate how the innovative assignment algorithm successfully assigns the undefined customers to appropriate multiple product affinity groups using nationwide retailer transactional data. In addition, the result shows that potential customers establish loyalty through migration from a single to multiple product affinity groups. This comprehensive and insightful business solution will be shared in this paper. Also, this paper provides a clustering algorithm and nonparametric tree model for model building. The customer assignment for using SAS macro code is provided in an appendix.
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Hsin-Yi Wang, Alliance Data Systems
Paper 2900-2015:
Multiple Ways to Detect Differential Item Functioning in SAS®
Differential item functioning (DIF), as an assessment tool, has been widely used in quantitative psychology, educational measurement, business management, insurance, and health care. The purpose of DIF analysis is to detect response differences of items in questionnaires, rating scales, or tests across different subgroups (for example, gender) and to ensure the fairness and validity of each item for those subgroups. The goal of this paper is to demonstrate several ways to conduct DIF analysis by using different SAS® procedures (PROC FREQ, PROC LOGISITC, PROC GENMOD, PROC GLIMMIX, and PROC NLMIXED) and their applications. There are three general methods to examine DIF: generalized Mantel-Haenszel (MH), logistic regression, and item response theory (IRT). The SAS® System provides flexible procedures for all these approaches. There are two types of DIF: uniform DIF, which remains consistent across ability levels, and non-uniform DIF, which varies across ability levels. Generalized MH is a nonparametric method and is often used to detect uniform DIF while the other two are parametric methods and examine both uniform and non-uniform DIF. In this study, I first describe the underlying theories and mathematical formulations for each method. Then I show the SAS statements, input data format, and SAS output for each method, followed by a detailed demonstration of the differences among the three methods. Specifically, PROC FREQ is used to calculate generalized MH only for dichotomous items. PROC LOGISITIC and PROC GENMOD are used to detect DIF by using logistic regression. PROC NLMIXED and PROC GLIMMIX are used to examine DIF by applying an exploratory item response theory model. Finally, I use SAS/IML® to call two R packages (that is, difR and lordif) to conduct DIF analysis and then compare the results between SAS procedures and R packages. An example data set, the Verbal Aggression assessment, which includes 316 subjects and 24 items, is used in this stud y. Following the general DIF analysis, the male group is used as the reference group, and the female group is used as the focal group. All the analyses are conducted by SAS® 9.3 and R 2.15.3. The paper closes with the conclusion that the SAS System provides different flexible and efficient ways to conduct DIF analysis. However, it is essential for SAS users to understand the underlying theories and assumptions of different DIF methods and apply them appropriately in their DIF analyses.
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Yan Zhang, Educational Testing Service
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Paper SAS1866-2015:
Now That You Have Your Data in Hadoop, How Are You Staging Your Analytical Base Tables?
Well, Hadoop community, now that you have your data in Hadoop, how are you staging your analytical base tables? In my discussions with clients about this, we all agree on one thing: Data sizes stored in Hadoop prevent us from moving that data to a different platform in order to generate the analytical base tables. To address this dilemma, I want to introduce to you the SAS® In-Database Code Accelerator for Hadoop.
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Steven Sober, SAS
Donna DeCapite, SAS
O
Paper 3296-2015:
Out of Control! A SAS® Macro to Recalculate QC Statistics
SAS/QC® provides procedures, such as PROC SHEWHART, to produce control charts with centerlines and control limits. When quality improvement initiatives create an out-of-control process of improvement, centerlines and control limits need to be recalculated. While this is not a complicated process, producing many charts with multiple centerline shifts can quickly become difficult. This paper illustrates the use of a macro to efficiently compute centerlines and control limits when one or more recalculations are needed for multiple charts.
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Jesse Pratt, Cincinnati Children's Hospital Medical Center
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Paper 3516-2015:
Piecewise Linear Mixed Effects Models Using SAS
Evaluation of the impact of critical or high-risk events or periods in longitudinal studies of growth might provide clues to the long-term effects of life events and efficacies of preventive and therapeutic interventions. Conventional linear longitudinal models typically involve a single growth profile to represent linear changes in an outcome variable across time, which sometimes does not fit the empirical data. The piecewise linear mixed-effects models allow different linear functions of time corresponding to the pre- and post-critical time point trends. This presentation shows: 1) how to perform piecewise linear mixed effects models using SAS step by step, in the context of a clinical trial with two-arm interventions and a predictive covariate of interest; 2) how to obtain the slopes and corresponding p-values for intervention and control groups during pre- and post-critical periods, conditional on different values of the predictive covariate; and 3) explains how to make meaningful comparisons and present results in a scientific manuscript. A SAS macro to generate the summary tables assisting the interpretation of the results is also provided.
Qinlei Huang, St Jude Children's Research Hospital
Paper 3307-2015:
Preparing Output from Statistical Procedures for Publication, Part 1: PROC REG to APA Format
Many scientific and academic journals require that statistical tables be created in a specific format, with one of the most common formats being that of the American Psychological Association (APA). The APA publishes a substantial guide book to writing and formatting papers, including an extensive section on creating tables (Nichol 2010). However, the output generated by SAS® procedures does not match this style. This paper discusses techniques to change the SAS procedure output to match the APA guidelines using SAS ODS (Output Delivery System).
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Vince DelGobbo, SAS
Peter Flom, Peter Flom Consulting
Paper 2863-2015:
"Puck Pricing": Dynamic Hockey Ticket Price Optimization
Dynamic pricing is a real-time strategy where corporations attempt to alter prices based on varying market demand. The hospitality industry has been doing this for quite a while, altering prices significantly during the summer months or weekends when demand for rooms is at a premium. In recent years, the sports industry has started to catch on to this trend, especially within Major League Baseball (MLB). The purpose of this paper is to explore the methodology of applying this type of pricing to the hockey ticketing arena.
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Christopher Jones, Deloitte Consulting
Sabah Sadiq, Deloitte Consulting
Jing Zhao, Deloitte Consulting LLP
Paper 3382-2015:
Put Your Data on the Map
A bubble map can be a useful tool for identifying trends and visualizing the geographic proximity and intensity of events. This session shows how to use PROC GEOCODE and PROC GMAP to turn a data set of addresses and events into a map of the United States with scaled bubbles depicting the location and intensity of the events.
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Caroline Cutting, Warren Rogers Associates
R
Paper 1341-2015:
Random vs. Fixed Effects: Which Technique More Effectively Addresses Selection Bias in Observational Studies
Retrospective case-control studies are frequently used to evaluate health care programs when it is not feasible to randomly assign members to a respective cohort. Without randomization, observational studies are more susceptible to selection bias where the characteristics of the enrolled population differ from those of the entire population. When the participant sample is different from the comparison group, the measured outcomes are likely to be biased. Given this issue, this paper discusses how propensity score matching and random effects techniques can be used to reduce the impact selection bias has on observational study outcomes. All results shown are drawn from an ROI analysis using a participant (cases) versus non-participant (controls) observational study design for a fitness reimbursement program aiming to reduce health care expenditures of participating members.
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Jess Navratil-Strawn, Optum
Paper SAS1941-2015:
Real Time--Is That Your Final Decision?
Streaming data is becoming more and more prevalent. Everything is generating data now--social media, machine sensors, the 'Internet of Things'. And you need to decide what to do with that data right now. And 'right now' could mean 10,000 times or more per second. SAS® Event Stream Processing provides an infrastructure for capturing streaming data and processing it on the fly--including applying analytics and deciding what to do with that data. All in milliseconds. There are some basic tenets on how SAS® provides this extremely high-throughput, low-latency technology to meet whatever streaming analytics your company might want to pursue.
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Diane Hatcher, SAS
Jerry Baulier, SAS
Steve Sparano, SAS
Paper 3740-2015:
Risk-Adjusting Provider Performance Utilization Metrics
Pay-for-performance programs are putting increasing pressure on providers to better manage patient utilization through care coordination, with the philosophy that good preventive services and routine care can prevent the need for some high-resource services. Evaluation of provider performance frequently includes measures such as acute care events (ER and inpatient), imaging, and specialist services, yet rarely are these indicators adjusted for the underlying risk of providers' patient panel. In part, this is because standard patient risk scores are designed to predict costs, not the probability of specific service utilization. As such, Blue Cross Blue Shield of North Carolina has developed a methodology to model our members' risk of these events in an effort to ensure that providers are evaluated fairly and to prevent our providers from adverse selection practices. Our risk modeling takes into consideration members' underlying health conditions and limited demographic factors during the previous 12 month period, and employs two-part regression models using SAS® software. These risk-adjusted measures will subsequently be the basis of performance evaluation of primary care providers for our Accountable Care Organizations and medical home initiatives.
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Stephanie Poley, Blue Cross Blue Shield of North Carolina
S
Paper SAS4800-2015:
SAS Certification Overview
Join us for lunch as we discuss the benefits of being part of the elite group that is SAS Certified Professionals. The SAS Global Certification program has awarded more than 79,000 credentials to SAS users across the globe. Come listen to Terry Barham, Global Certification Manager, give an overview of the SAS Certification program, explain the benefits of becoming SAS certified and discuss exam preparation tips. This session will also include a Q&A section where you can get answers to your SAS Certification questions.
Paper SAS4283-2015:
SAS Retail Roadmap
The goal of this presentation is to provide user group an update on retail solution releases in past one year and the roadmap moving forward.
Saurabh Gupta, SAS
Paper SAS1940-2015:
SAS/STAT® 14.1: Methods for Massive, Missing, or Multifaceted Data
The latest release of SAS/STAT® software brings you powerful techniques that will make a difference in your work, whether your data are massive, missing, or somewhere in the middle. New imputation software for survey data adds to an expansive array of methods in SAS/STAT for handling missing data, as does the production version of the GEE procedure, which provides the weighted generalized estimating equation approach for longitudinal studies with dropouts. An improved quadrature method in the GLIMMIX procedure gives you accelerated performance for certain classes of models. The HPSPLIT procedure provides a rich set of methods for statistical modeling with classification and regression trees, including cross validation and graphical displays. The HPGENSELECT procedure adds support for spline effects and lasso model selection for generalized linear models. And new software implements generalized additive models by using an approach that handles large data easily. Other updates include key functionality for Bayesian analysis and pharmaceutical applications.
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Maura Stokes, SAS
Bob Rodriguez, SAS
Paper SAS1907-2015:
SAS® Data Management: Technology Options for Ensuring a Quality Journey Through the Data Management Process
When planning for a journey, one of the main goals is to get the best value possible. The same thing could be said for your corporate data as it journeys through the data management process. It is your goal to get the best data in the hands of decision makers in a timely fashion, with the lowest cost of ownership and the minimum number of obstacles. The SAS® Data Management suite of products provides you with many options for ensuring value throughout the data management process. The purpose of this session is to focus on how the SAS® Data Management solution can be used to ensure the delivery of quality data, in the right format, to the right people, at the right time. The journey is yours, the technology is ours--together, we can make it a fulfilling and rewarding experience.
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Mark Craver, SAS
Paper SAS2520-2015:
SAS® Does Data Science: How to Succeed in a Data Science Competition
First introduced in 2013, the Cloudera Data Science Challenge is a rigorous competition in which candidates must provide a solution to a real-world big data problem that surpasses a benchmark specified by some of the world's elite data scientists. The Cloudera Data Science Challenge 2 (in 2014) involved detecting anomalies in the United States Medicare insurance system. Finding anomalous patients, procedures, providers, and regions in the competition's large, complex, and intertwined data sets required industrial-strength tools for data wrangling and machine learning. This paper shows how I did it with SAS®.
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Patrick Hall, SAS
Paper SAS4083-2015:
SAS® Workshop: Data Mining
This workshop provides hands-on experience using SAS® Enterprise Miner. Workshop participants will learn to: open a project, create and explore a data source, build and compare models, and produce and examine score code that can be used for deployment.
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Chip Wells, SAS
Paper SAS4082-2015:
SAS® Workshop: Forecasting
This workshop provides hands-on experience using SAS® Forecast Server. Workshop participants will learn to: create a project with a hierarchy, generate multiple forecast automatically, evaluate the forecasts accuracy, and build a custom model.
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Catherine Truxillo, SAS
George Fernandez, SAS
Terry Woodfield, SAS
Paper SAS4280-2015:
SAS® Workshop: SAS Data Loader for Hadoop
This workshop provides hands-on experience with SAS® Data Loader for Hadoop. Workshop participants will configure SAS Data Loader for Hadoop and use various directives inside SAS Data Loader for Hadoop to interact with data in the Hadoop cluster.
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Kari Richardson, SAS
Paper SAS4120-2015:
SAS® Workshop: SAS® Visual Analytics
This workshop provides hands-on experience with SAS® Visual Analytics. Workshop participants will explore data with SAS® Visual Analytics Explorer and design reports with SAS® Visual Analytics Designer.
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Nicole Ball, SAS
Paper SAS4081-2015:
SAS® Workshop: SAS® Visual Statistics 7.1
This workshop provides hands-on experience with SAS® Visual Statistics. Workshop participants will learn to: move between the Visual Analytics Explorer interface and Visual Statistics, fit automatic statistical models, create exploratory statistical analysis, compare models using a variety of metrics, and create score code.
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Catherine Truxillo, SAS
Xiangxiang Meng, SAS
Mike Jenista, SAS
Paper SAS4084-2015:
SAS® Workshop: Text Analytics
This workshop provides hands-on experience using SAS® Text Miner. Workshop participants will learn to: read a collection of text documents and convert them for use by SAS Text Miner using the Text Import node, use the simple query language supported by the Text Filter node to extract information from a collection of documents, use the Text Topic node to identify the dominant themes and concepts in a collection of documents, and use the Text Rule Builder node to classify documents having pre-assigned categories.
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Terry Woodfield, SAS
Paper SAS1856-2015:
SAS® and SAP Business Warehouse on SAP HANA--What's in the Handshake?
Is your company using or considering using SAP Business Warehouse (BW) powered by SAP HANA? SAS® provides various levels of integration with SAP BW in an SAP HANA environment. This integration enables you to not only access SAP BW components from SAS, but to also push portions of SAS analysis directly into SAP HANA, accelerating predictive modeling and data mining operations. This paper explains the SAS toolset for different integration scenarios, highlights the newest technologies contributing to integration, and walks you through examples of using SAS with SAP BW on SAP HANA. The paper is targeted at SAS and SAP developers and architects interested in building a productive analytical environment with the help of the latest SAS and SAP collaborative advancements.
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Tatyana Petrova, SAS
Paper 2687-2015:
Selection and Transformation of Continuous Predictors for Logistic Regression
This paper discusses the selection and transformation of continuous predictor variables for the fitting of binary logistic models. The paper has two parts: (1) A procedure and associated SAS® macro are presented that can screen hundreds of predictor variables and 10 transformations of these variables to determine their predictive power for a logistic regression. The SAS macro passes the training data set twice to prepare the transformations and one more time through PROC TTEST. (2) The FSP (function selection procedure) and a SAS implementation of FSP are discussed. The FSP tests all transformations from among a class of FSP transformations and finds the one with maximum likelihood when fitting the binary target. In a 2008 book, Patrick Royston and Willi Sauerbrei popularized the FSP.
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Bruce Lund, Marketing Associates, LLC
Paper 3209-2015:
Standardizing the Standardization Process
A prevalent problem surrounding Extract, Transform, and Load (ETL) development is the ability to apply consistent logic and manipulation of source data when migrating to target data structures. Certain inconsistencies that add a layer of complexity include, but are not limited to, naming conventions and data types associated with multiple sources, numerous solutions applied by an array of developers, and multiple points of updating. In this paper, we examine the evolution of implementing a best practices solution during the process of data delivery, with respect to standardizing data. The solution begins with injecting the transformations of the data directly into the code at the standardized layer via Base SAS® or SAS® Enterprise Guide®. A more robust method that we explore is to apply these transformations with SAS® macros. This provides the capability to apply these changes in a consistent manner across multiple sources. We further explore this solution by implementing the macros within SAS® Data Integration Studio processes on the DataFlux® Data Management Platform. We consider these issues within the financial industry, but the proposed solution can be applied across multiple industries.
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Avery Long, Financial Risk Group
Frank Ferriola, Financial Risk Group
Paper SAS1864-2015:
Statistics for Gamers--Using SAS® Visual Analytics and SAS® Visual Statistics to Analyze World of Warcraft Logs
Video games used to be child's play. Today, millions of gamers of all ages kill countless in-game monsters and villains every day. Gaming is big business, and the data it generates is even bigger. Massive multi-player online games like World of Warcraft by Blizzard Entertainment not only generate data that Blizzard Entertainment can use to monitor users and their environments, but they can also be set up to log player data and combat logs client-side. Many users spend time analyzing their playing 'rotations' and use the information to adjust their playing style to deal more damage or, more appropriately, to heal themselves and other players. This paper explores World of Warcraft logs by using SAS® Visual Analytics and applies statistical techniques by using SAS® Visual Statistics to discover trends.
Mary Osborne, SAS
Adam Maness
Paper 1521-2015:
Sums of Squares: The Basics and a Surprise
Most 'Design of Experiment' textbooks cover Type I, Type II, and Type III sums of squares, but many researchers and statisticians fall into the habit of using one type mindlessly. This breakout session reviews the basics and illustrates the importance of the choice of type as well as the variable definitions in PROC GLM and PROC REG.
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Sheila Barron, University of Iowa
Michelle Mengeling, Comprehensive Access & Delivery Research & Evaluation-CADRE, Iowa City VA Health Care System
T
Paper SAS2604-2015:
Take a Bite Out of Crime with SAS® Visual Scenario Designer
The vast and increasing demands of fraud detection and description have promoted the broad application of statistics and machine learning in fields as diverse as banking, credit card application and usage, insurance claims, trader surveillance, health care claims, and government funding and allowance management. SAS® Visual Scenario Designer enables you to derive interactive business rules, along with descriptive and predictive models, to detect and describe fraud. This paper focuses on building interactive decision trees to classify fraud. Attention to optimizing the feature space (candidate predictors) prior to modeling is also covered. Because big data plays an increasingly vital role in fraud detection and description, SAS Visual Scenario Designer leverages the in-memory, parallel, and distributed computing abilities of SAS® LASR™ Analytic Server as a back end to support real-time performance on massive amounts of data.
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Yue Qi, SAS
Paper SAS1387-2015:
Ten Tips for Simulating Data with SAS®
Data simulation is a fundamental tool for statistical programmers. SAS® software provides many techniques for simulating data from a variety of statistical models. However, not all techniques are equally efficient. An efficient simulation can run in seconds, whereas an inefficient simulation might require days to run. This paper presents 10 techniques that enable you to write efficient simulations in SAS. Examples include how to simulate data from a complex distribution and how to use simulated data to approximate the sampling distribution of a statistic.
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Rick Wicklin, SAS
Paper 3488-2015:
Text Analytics on Electronic Medical Record Data
This session describes our journey from data acquisition to text analytics on clinical, textual data.
Mark Pitts, Highmark Health
Paper 2920-2015:
Text Mining Kaiser Permanente Member Complaints with SAS® Enterprise Miner™
This presentation details the steps involved in using SAS® Enterprise Miner™ to text mine a sample of member complaints. Specifically, it describes how the Text Parsing, Text Filtering, and Text Topic nodes were used to generate topics that described the complaints. Text mining results are reviewed (slightly modified for confidentiality), as well as conclusions and lessons learned from the project.
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Amanda Pasch, Kaiser Permanenta
Paper 3860-2015:
The Challenges with Governing Big Data: How SAS® Can Help
In this session, I discuss an overall approach to governing Big Data. I begin with an introduction to Big Data governance and the governance framework. Then I address the disciplines of Big Data governance: data ownership, metadata, privacy, data quality, and master and reference data management. Finally, I discuss the reference architecture of Big Data, and how SAS® tools can address Big Data governance.
Sunil Soares, Information Asset
Paper 3060-2015:
The Knight's Tour in Chess--Implementing a Heuristic Solution
The knight's tour is a sequence of moves on a chess board such that a knight visits each square only once. Using a heuristic method, it is possible to find a complete path, beginning from any arbitrary square on the board and landing on the remaining squares only once. However, the implementation poses challenging programming problems. For example, it is necessary to discern viable knight moves, which change throughout the tour. Even worse, the heuristic approach does not guarantee a solution. This paper explains a SAS® solution that finds a knight's tour beginning from every initial square on a chess board...well, almost.
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John R Gerlach, Dataceutics, Inc.
Paper SPON3000-2015:
The New Analytics Experience at SAS®--an Analytics Culture Driven by Millennials
This unique culture has access to lots of data, unstructured and structured; is innovative, experimental, groundbreaking, and doesn't follow convention; and has access to powerful new infrastructure technologies and scalable, industry-standard computing power like never seen before. The convergence of data, and innovative spirit, and the means to process it is what makes this a truly unique culture. In response to that, SAS® proposes The New Analytics Experience. Attend this session to hear more about the New Analytics Experience and the latest Intel technologies that make it possible.
Mark Pallone, Intel
Paper 3741-2015:
The Spatio-Temporal Impact of Urgent Care Centers on Physician and ER Use
The unsustainable trend in healthcare costs has led to efforts to shift some healthcare services to less expensive sites of care. In North Carolina, the expansion of urgent care centers introduces the possibility that non-emergent and non-life threatening conditions can be treated at a less intensive care setting. BCBSNC conducted a longitudinal study of density of urgent care centers, primary care providers, and emergency departments, and the differences in how members access care near those locations. This talk focuses on several analytic techniques that were considered for the analysis. The model needed to account for the complex relationship between the changes in the population (including health conditions and health insurance benefits) and the changes in the types of services and supply of services offered by healthcare providers proximal to them. Results for the chosen methodology are discussed.
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Laurel Trantham, Blue Cross and Blue Shield North Carolina
Paper 3820-2015:
Time to Harvest: Operationalizing SAS® Analytics on the SAP HANA Platform
A maximum harvest in farming analytics is achieved only if analytics can also be operationalized at the level of core business applications. Mapped to the use of SAS® Analytics, the fruits of SAS be shared with Enterprise Business Applications by SAP. Learn how your SAS environment, including the latest of SAS® In-Memory Analytics, can be integrated with SAP applications based on the SAP In-Memory Platform SAP HANA. We'll explore how a SAS® Predictive Modeling environment can be embedded inside SAP HANA and how native SAP HANA data management capabilities such as SAP HANA Views, Smart Data Access, and more can be leveraged by SAS applications and contribute to an end-to-end in-memory data management and analytics platform. Come and see how you can extend the reach of your SAS® Analytics efforts with the SAP HANA integration!
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Morgen Christoph, SAP SE
Paper 3081-2015:
Tweet-O-Matic: An Automated Approach to Batch Processing of Tweets
Currently, there are several methods for reading JSON formatted files into SAS® that depend on the version of SAS and which products are licensed. These methods include user-defined macros, visual analytics, PROC GROOVY, and more. The user-defined macro %GrabTweet, in particular, provides a simple way to directly read JSON-formatted tweets into SAS® 9.3. The main limitation of %GrabTweet is that it requires the user to repeatedly run the macro in order to download large amounts of data over time. Manually downloading tweets while conforming to the Twitter rate limits might cause missing observations and is time-consuming overall. Imagine having to sit by your computer the entire day to continuously grab data every 15 minutes, just to download a complete data set of tweets for a popular event. Fortunately, the %GrabTweet macro can be modified to automate the retrieval of Twitter data based on the rate that the tweets are coming in. This paper describes the application of the %GrabTweet macro combined with batch processing to download tweets without manual intervention. Users can specify the phrase parameters they want, run the batch processing macro, leave their computer to automatically download tweets overnight, and return to a complete data set of recent Twitter activity. The batch processing implements an automated retrieval of tweets through an algorithm that assesses the rate of tweets for the specified topic in order to make downloading large amounts of data simpler and effortless for the user.
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Isabel Litton, California Polytechnic State University, SLO
Rebecca Ottesen, City of Hope and Cal Poly SLO
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Paper SAS1910-2015:
Unconventional Data-Driven Methodologies Forecast Performance in Unconventional Oil and Gas Reservoirs
How does historical production data relate a story about subsurface oil and gas reservoirs? Business and domain experts must perform accurate analysis of reservoir behavior using only rate and pressure data as a function of time. This paper introduces innovative data-driven methodologies to forecast oil and gas production in unconventional reservoirs that, owing to the nature of the tightness of the rocks, render the empirical functions less effective and accurate. You learn how implementations of the SAS® MODEL procedure provide functional algorithms that generate data-driven type curves on historical production data. Reservoir engineers can now gain more insight to the future performance of the wells across their assets. SAS enables a more robust forecast of the hydrocarbons in both an ad hoc individual well interaction and in an automated batch mode across the entire portfolio of wells. Examples of the MODEL procedure arising in subsurface production data analysis are discussed, including the Duong data model and the stretched exponential data model. In addressing these examples, techniques for pattern recognition and for implementing TREE, CLUSTER, and DISTANCE procedures in SAS/STAT® are highlighted to explicate the importance of oil and gas well profiling to characterize the reservoir. The MODEL procedure analyzes models in which the relationships among the variables comprise a system of one or more nonlinear equations. Primary uses of the MODEL procedure are estimation, simulation, and forecasting of nonlinear simultaneous equation models, and generating type curves that fit the historical rate production data. You will walk through several advanced analytical methodologies that implement the SEMMA process to enable hypotheses testing as well as directed and undirected data mining techniques. SAS® Visual Analytics Explorer drives the exploratory data analysis to surface trends and relationships, and the data QC workflows ensure a robust input space for the performance forecasting methodologies that are visualized in a web-based thin client for interactive interpretation by reservoir engineers.
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Keith Holdaway, SAS
Louis Fabbi, SAS
Dan Lozie, SAS
Paper 1640-2015:
Understanding Characteristics of Insider Threats by Using Feature Extraction
This paper explores feature extraction from unstructured text variables using Term Frequency-Inverse Document Frequency (TF-IDF) weighting algorithms coded in Base SAS®. Data sets with unstructured text variables can often hold a lot of potential to enable better predictive analysis and document clustering. Each of these unstructured text variables can be used as inputs to build an enriched data set-specific inverted index, and the most significant terms from this index can be used as single word queries to weight the importance of the term to each document from the corpus. This paper also explores the usage of hash objects to build the inverted indices from the unstructured text variables. We find that hash objects provide a considerable increase in algorithm efficiency, and our experiments show that a novel weighting algorithm proposed by Paik (2013) best enables meaningful feature extraction. Our TF-IDF implementations are tested against a publicly available data breach data set to understand patterns specific to insider threats to an organization.
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Ila Gokarn, Singapore Management University
Clifton Phua, SAS
Paper 3333-2015:
Understanding Patient Populations in New Hampshire using SAS® Visual Analytics
The NH Citizens Health Initiative and the University of New Hampshire Institute for Health Policy and Practice, in collaboration with Accountable Care Project (ACP) participants, have developed a set of analytic reports to provide systems undergoing transformation a capacity to compare performance on the measures of quality, utilization, and cost across systems and regions. The purpose of these reports is to provide data and analysis on which our ACP learning collaborative can share knowledge and develop action plans that can be adopted by health-care innovators in New Hampshire. This breakout session showcases the claims-based reports, powered by SAS® Visual Analytics and driven by the New Hampshire Comprehensive Health Care Information System (CHIS), which includes commercial, Medicaid, and Medicare populations. With the power of SAS Visual Analytics, hundreds of pages of PDF files were distilled down to a manageable, dynamic, web-based portal that allows users to target information most appealing to them. This streamlined approach reduces barriers to obtaining information, offers that information in a digestible medium, and creates a better user experience. For more information about the ACP or to access the public reports, visit http://nhaccountablecare.org/.
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Danna Hourani, SAS
Paper 3408-2015:
Understanding Patterns in the Utilization and Costs of Elbow Reconstruction Surgeries: A Healthcare Procedure that is Common among Baseball Pitchers
Athletes in sports, such as baseball and softball, commonly undergo elbow reconstruction surgeries. There is research that suggests that the rate of elbow reconstruction surgeries among professional baseball pitchers continues to rise by leaps and bounds. Given the trend found among professional pitchers, the current study reviews patterns of elbow reconstruction surgery among the privately insured population. The study examined trends (for example, cost, age, geography, and utilization) in elbow reconstruction surgeries among privately insured patients using analytic tools such as SAS® Enterprise Guide® and SAS® Visual Analytics, based on the medical and surgical claims data from the FAIR Health National Private Insurance Claims (NPIC) database. The findings of the study suggested that there are discernable patterns in the prevalence of elbow reconstruction surgeries over time and across specific geographic regions.
Read the paper (PDF). | Download the data file (ZIP).
Jeff Dang, FAIR Health
Paper 3141-2015:
Unstructured Data Mining to Improve Customer Experience in Interactive Voice Response Systems
Interactive Voice Response (IVR) systems are likely one of the best and worst gifts to the world of communication, depending on who you ask. Businesses love IVR systems because they take out hundreds of millions of dollars of call center costs in automation of routine tasks, while consumers hate IVRs because they want to talk to an agent! It is a delicate balancing act to manage an IVR system that saves money for the business, yet is smart enough to minimize consumer abrasion by knowing who they are, why they are calling, and providing an easy automated solution or a quick route to an agent. There are many aspects to designing such IVR systems, including engineering, application development, omni-channel integration, user interface design, and data analytics. For larger call volume businesses, IVRs generate terabytes of data per year, with hundreds of millions of rows per day that track all system and customer- facing events. The data is stored in various formats and is often unstructured (lengthy character fields that store API return information or text fields containing consumer utterances). The focus of this talk is the development of a data mining framework based on SAS® that is used to parse and analyze IVR data in order to provide insights into usability of the application across various customer segments. Certain use cases are also provided.
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Dmitriy Khots, West Corp
Paper 3339-2015:
Using Analytics To Help Win The Presidential Election
In 2012, the Obama campaign used advanced analytics to target voters, especially in social media channels. Millions of voters were scored on models each night to predict their voting patterns. These models were used as the driver for all campaign decisions, including TV ads, budgeting, canvassing, and digital strategies. This presentation covers how the Obama campaign strategies worked, what's in store for analytics in future elections, and how these strategies can be applied in the business world.
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Peter Tanner, Capital One
Paper 4640-2015:
Using Analytics to Become The USA Memory Champion
Becoming one of the best memorizers in the world doesn't happen overnight. With hard work, dedication, a bit of obsession, and with the assistance of some clever analytics metrics, Nelson Dellis was able to climb himself up to the top of the memory rankings in under a year to become the now 3x USA Memory Champion. In this talk, he explains what it takes to become the best at memory, what is involved in such grueling memory competitions, and how analytics helped him get there.
Nelson Dellis, Climb for Memory
Paper 2740-2015:
Using Heat Maps to Compare Clusters of Ontario DWI Drivers
SAS® PROC FASTCLUS generates five clusters for the group of repeat clients of Ontario's Remedial Measures program. Heat map tables are shown for selected variables such as demographics, scales, factor, and drug use to visualize the difference between clusters.
Rosely Flam-Zalcman, CAMH
Robert Mann, CAM
Rita Thomas, CAMH
Paper 3208-2015:
Using SAS/STAT® Software to Implement a Multivariate Aadaptive Outlier Detection Approach to Distinguish Outliers from Extreme Values
Hawkins (1980) defines an outlier as an observation that deviates so much from other observations as to arouse the suspicion that it was generated by a different mechanism . To identify data outliers, a classic multivariate outlier detection approach implements the Robust Mahalanobis Distance Method by splitting the distribution of distance values into two subsets (within-the-norm and out-of-the-norm), with the threshold value usually set to the 97.5% quantile of the Chi-Square distribution with p (number of variables) degrees of freedom and items whose distance values are beyond it are labeled out-of-the-norm. This threshold value is an arbitrary number, however, and it might flag as out-of-the-norm a number of items that are actually extreme values of the baseline distribution rather than outliers. Therefore, it is desirable to identify an additional threshold, a cutoff point that divides the set of out-of-norm points in two subsets--extreme values and outliers. One way to do this--in particular for larger databases--is to Increase the threshold value to another arbitrary number, but this approach requires taking into consideration the size of the data set since size affects the threshold-separating outliers from extreme values. A 2003 article by Gervini (Journal of Multivariate Statistics) proposes an adaptive threshold that increases with the number of items n if the data is clean but it remains bounded if there are outliers in the data. In 2005 Filzmoser, Garrett, and Reimann (Computers & Geosciences) built on Gervini's contribution to derive by simulation a relationship between the number of items n, the number of variables in the data p, and a critical ancillary variable for the determination of outlier thresholds. This paper implements the Gervini adaptive threshold value estimator by using PROC ROBUSTREG and the SAS® Chi-Square functions CINV and PROBCHI, available in the SAS/STAT® environment. It also provides data simulations to illustrate the reliab ility and the flexibility of the method in distinguishing true outliers from extreme values.
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Paulo Macedo, Integrity Management Services, LLC
Paper 3202-2015:
Using SAS® Mapping Functionality to Measure and Present the Veracity of Location Data
Crowd sourcing of data is growing rapidly, enabled by smart devices equipped with assisted GPS location, tagging of photos, and mapping other aspects of the users' lives and activities. A fundamental assumption that the reported locations are accurate within the usual GPS limitations of approximately 10m is made when such data is used. However, as a result of a wide range of technical issues, it turns out that the accuracy of the reported locations is highly variable and cannot be relied on; some locations are accurate but many are highly inaccurate, and that can affect many of the decisions that are being made based on the data. An analysis of a set of data is presented that demonstrates that this assumption is flawed, and examples of the levels of inaccuracy that has significant consequences in a range of contexts are provided. By using Base SAS®, the paper demonstrates the quality and veracity of the data and the scale of the errors that can be present. This analysis has critical significance in fields such as mobile location-based marketing, forensics, and law.
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Richard Self, University of Derby
Paper 3440-2015:
Using SAS® Text Analytics to Examine Gubernatorial Rhetoric and Mass Incarceration
Throughout the latter part of the twentieth century, the United States of America has experienced an incredible boom in the rate of incarceration of its citizens. This increase arguably began in the 1970s when the Nixon administration oversaw the beginning of the war on drugs in America. The U.S. now has one of the highest rates of incarceration among industrialized nations. However, the citizens who have been incarcerated on drug charges have disproportionately been African American or other racial minorities, even though many studies have concluded that drug use is fairly equal among racial groups. In order to remedy this situation, it is essential to first understand why so many more people have been arrested and incarcerated. In this research, I explore a potential explanation for the epidemic of mass incarceration. I intend to answer the question does gubernatorial rhetoric have an effect on the rate of incarceration in a state? More specifically, I am interested in examining the language that the governor of a state uses at the annual State of the State address in order to see if there is any correlation between rhetoric and the subsequent rate of incarceration in that state. In order to understand any possible correlation, I use SAS® Text Miner and SAS® Contextual Analysis to examine the attitude towards crime in each speech. The political phenomenon that I am trying to understand is how state government employees are affected by the tone that the chief executive of a state uses towards crime, and whether the actions of these state employees subsequently lead to higher rates of incarceration. The governor is the top government official in charge of employees of a state, so when this official addresses the state, the employees may take the governor's message as an order for how they do their jobs. While many political factors can affect legislation and its enforcement, a governor has the ability to set the tone of a state when it comes to policy issues suc h as crime.
Catherine Lachapelle, UNC Chapel Hill
Paper 3212-2015:
Using SAS® to Combine Regression and Time Series Analysis on U.S. Financial Data to Predict the Economic Downturn
During the financial crisis of 2007-2009, the U.S. labor market lost 8.4 million jobs, causing the unemployment rate to increase from 5% to 9.5%. One of the indicators for economic recession is negative gross domestic product (GDP) for two consecutive quarters. This poster combines quantitative and qualitative techniques to predict the economic downturn by forecasting recession probabilities. Data was collected from the Board of Governors of the Federal Reserve System and the Federal Reserve Bank of St. Louis, containing 29 variables and quarterly observations from 1976-Q1 to 2013-Q3. Eleven variables were selected as inputs based on their effects on recession and limiting the multicollinearity: long-term treasury yield (5-year and 10-year), mortgage rate, CPI inflation rate, prime rate, market volatility index, Better Business Bureau (BBB) corporate yield, house price index, stock market index, commercial real estate price index, and one calculated variable yield spread (Treasury yield-curve spread). The target variable was a binary variable depicting the economic recession for each quarter (1=Recession). Data was prepared for modeling by applying imputation and transformation on variables. Two-step analysis was used to forecast the recession probabilities for the short-term period. Predicted recession probabilities were first obtained from the Backward Elimination Logistic Regression model that was selected on the basis of misclassification (validation misclassification= 0.115). These probabilities were then forecasted using the Exponential Smoothing method that was selected on the basis of mean average error (MAE= 11.04). Results show the recession periods including the great recession of 2008 and the forecast for eight quarters (up to 2015-Q3).
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Avinash Kalwani, Oklahoma State University
Nishant Vyas, Oklahoma State University
Paper 3508-2015:
Using Text from Repair Tickets of a Truck Manufacturing Company to Predict Factors that Contribute to Truck Downtime
In this era of bigdata, the use of text analytics to discover insights is rapidly gainingpopularity in businesses. On average, more than 80 percent of the data inenterprises may be unstructured. Text analytics can help discover key insightsand extract useful topics and terms from the unstructured data. The objectiveof this paper is to build a model using textual data that predicts the factorsthat contribute to downtime of a truck. This research analyzes the data of over200,000 repair tickets of a leading truck manufacturing company. After theterms were grouped into fifteen key topics using text topic node of SAS® TextMiner, a regression model was built using these topics to predict truckdowntime, the target variable. Data was split into training and validation fordeveloping the predictive models. Knowledge of the factors contributing todowntime and their associations helped the organization to streamline theirrepair process and improve customer satisfaction.
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Ayush Priyadarshi, Oklahoma State University
Goutam Chakraborty, Oklahoma State University
Paper 3644-2015:
Using and Understanding the LSMEANS and LSMESTIMATE Statements
The concept of least squares means, or population marginal means, seems to confuse a lot of people. We explore least squares means as implemented by the LSMEANS statement in SAS®, beginning with the basics. Particular emphasis is paid to the effect of alternative parameterizations (for example, whether binary variables are in the CLASS statement) and the effect of the OBSMARGINS option. We use examples to show how to mimic LSMEANS using ESTIMATE statements and the advantages of the relatively new LSMESTIMATE statement. The basics of estimability are discussed, including how to get around the dreaded non-estimable messages. Emphasis is put on using the STORE statement and PROC PLM to test hypotheses without having to redo all the model calculations. This material is appropriate for all levels of SAS experience, but some familiarity with linear models is assumed.
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David Pasta, ICON Clinical Research
Paper 1335-2015:
Using the GLIMMIX and GENMOD Procedures to Analyze Longitudinal Data from a Department of Veterans Affairs Multisite Randomized Controlled Trial
Many SAS® procedures can be used to analyze longitudinal data. This study employed a multisite randomized controlled trial design to demonstrate the effectiveness of two SAS procedures, GLIMMIX and GENMOD, to analyze longitudinal data from five Department of Veterans Affairs Medical Centers (VAMCs). Older male veterans (n = 1222) seen in VAMC primary care clinics were randomly assigned to two behavioral health models, integrated (n = 605) and enhanced referral (n = 617). Data was collected at baseline, and at 3-, 6-, and 12- month follow-up. A mixed-effects repeated measures model was used to examine the dependent variable, problem drinking, which was defined as count and dichotomous from baseline to 12 month follow-up. Sociodemographics and depressive symptoms were included as covariates. First, bivariate analyses included general linear model and chi-square tests to examine covariates by group and group by problem drinking outcomes. All significant covariates were included in the GLIMMIX and GENMOD models. Then, multivariate analysis included mixed models with Generalized Estimation Equations (GEEs). The effect of group, time, and the interaction effect of group by time were examined after controlling for covariates. Multivariate results were inconsistent for GLIMMIX and GENMOD using Lognormal, Gaussian, Weibull, and Gamma distributions. SAS is a powerful statistical program in data analyses for longitudinal study.
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Abbas Tavakoli, University of South Carolina/College of Nursing
Marlene Al-Barwani, University of South Carolina
Sue Levkoff, University of South Carolina
Selina McKinney, University of South Carolina
Nikki Wooten, University of South Carolina
Paper SAS1855-2015:
Using the PHREG Procedure to Analyze Competing-Risks Data
Competing risks arise in studies in which individuals are subject to a number of potential failure events and the occurrence of one event might impede the occurrence of other events. For example, after a bone marrow transplant, a patient might experience a relapse or might die while in remission. You can use one of the standard methods of survival analysis, such as the log-rank test or Cox regression, to analyze competing-risks data, whereas other methods, such as the product-limit estimator, might yield biased results. An increasingly common practice of assessing the probability of a failure in competing-risks analysis is to estimate the cumulative incidence function, which is the probability subdistribution function of failure from a specific cause. This paper discusses two commonly used regression approaches for evaluating the relationship of the covariates to the cause-specific failure in competing-risks data. One approach models the cause-specific hazard, and the other models the cumulative incidence. The paper shows how to use the PHREG procedure in SAS/STAT® software to fit these models.
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Ying So, SAS
Paper 3376-2015:
Using the SAS-PIRT Macro for Estimating the Parameters of Polytomous Items
Polytomous items have been widely used in educational and psychological settings. As a result, the demand for statistical programs that estimate the parameters of polytomous items has been increasing. For this purpose, Samejima (1969) proposed the graded response model (GRM), in which category characteristic curves are characterized by the difference of the two adjacent boundary characteristic curves. In this paper, we show how the SAS-PIRT macro (a SAS® macro written in SAS/IML®) was developed based on the GRM and how it performs in recovering the parameters of polytomous items using simulated data.
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Sung-Hyuck Lee, ACT, Inc.
V
Paper SAS1888-2015:
Visualizing Clinical Trial Data: Small Data, Big Insights
Data visualization is synonymous with big data, for which billions of records and millions of variables are analyzed simultaneously. But that does not mean data scientists analyzing clinical trial data that include only thousands of records and hundreds of variables cannot take advantage of data visualization methodologies. This paper presents a comprehensive process for loading standard clinical trial data into SAS® Visual Analytics, an interactive analytic solution. The process implements template reporting for a wide variety of point-and-click visualizations. Data operations required to support this reporting are explained and examples of the actual visualizations are presented so that users can implement this reporting using their own data.
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Michael Drutar, SAS
Elliot Inman, SAS
Paper 3486-2015:
Visualizing Student Enrollment Trends Compared across Calendar Periods and Grouped by Categories with SAS® Visual Analytics
Enrollment management is very important to all colleges. Having the correct tools to help you better understand your enrollment patterns of the past and the future is critical to any school. This session will describe how Valencia College went from manually updating static charts for enrollment management, to building dynamic, interactive visualizations to compare how students register across different calendar-date periods (current versus previous period)grouped by different start-of-registration dates--from start of registration, days into registration, and calendar date to previous year calendar date. This includes being able to see the trend by college campus, instructional method mode (onsite or online ) or by type of session (part of semester, full, and so on) all available in one visual and sliced and diced via check lists. The trend loads 4-6 million rows of data nightly to the SAS® LASR™ Analytics Server in a snap with no performance issues on the back-end or presentation visual. We will give a brief history of how we used to load data into Excel and manually build charts. Then we will describe the current environment, which is an automated approach through SAS® Visual Analytics. We will show pictures of our old, static reports, and then show the audience the power and functionality of our new, interactive reports through SAS Visual Analytics.
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Juan Olvera, Valencia College
W
Paper SAS1440-2015:
Want an Early Picture of the Data Quality Status of Your Analysis Data? SAS® Visual Analytics Shows You How
When you are analyzing your data and building your models, you often find out that the data cannot be used in the intended way. Systematic pattern, incomplete data, and inconsistencies from a business point of view are often the reason. You wish you could get a complete picture of the quality status of your data much earlier in the analytic lifecycle. SAS® analytics tools like SAS® Visual Analytics help you to profile and visualize the quality status of your data in an easy and powerful way. In this session, you learn advanced methods for analytic data quality profiling. You will see case studies based on real-life data, where we look at time series data from a bird's-eye-view and interactively profile GPS trackpoint data from a sail race.
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Gerhard Svolba, SAS
Paper 3600-2015:
When Two Are Better Than One: Fitting Two-Part Models Using SAS
In many situations, an outcome of interest has a large number of zero outcomes and a group of nonzero outcomes that are discrete or highly skewed. For example, in modeling health care costs, some patients have zero costs, and the distribution of positive costs are often extremely right-skewed. When modeling charitable donations, many potential donors give nothing, and the majority of donations are relatively small with a few very large donors. In the analysis of count data, there are also times where there are more zeros than would be expected using standard methodology, or cases where the zeros might differ substantially than the non-zeros, such as number of cavities a patient has at a dentist appointment or number of children born to a mother. If data has such structure, and ordinary least squares methods are used, then predictions and estimation might be inaccurate. The two-part model gives us a flexible and useful modeling framework in many situations. Methods for fitting the models with SAS® software are illustrated.
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Laura Kapitula, Grand Valley State University
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