One-Way Frequencies Task

About the One-Way Frequencies Task

The One-Way Frequencies task generates frequency tables from your data. You can also use this task to perform binomial and chi-square tests.
You might want to use this task to analyze the efficiency of a new drug. For example, suppose a group of medical researchers are interested in evaluating the efficacy of a new treatment for a skin condition. Dermatologists from participating clinics are trained to conduct the study and to evaluate the condition. After the training, two dermatologists examine patients with the skin condition from a pilot study and rate the same patients. The One-Way Frequencies task can be used to evaluate the agreement of the diagnoses.

Example: One-Way Frequencies of Unit Sales

In this example, you want to analyze unit sales for each sales region.
To create this example:
  1. In the Tasks section, expand the Statistics folder and double-click One-Way Frequencies. The user interface for the One-Way Frequencies task opens.
  2. On the Data tab, select the SASHELP.PRICEDATA data set.
  3. Assign columns to these roles:
    Role
    Column Name
    Analysis variables
    sale
    Group analysis by
    regionName
  4. To run the task, click Submit SAS code.
Here is a subset of the results:
Frequencies for Unit Sale

Assigning Data to Roles

To run the One-Way Frequencies task, you must assign a column to the Analysis variables role.
Role
Description
Roles
Analysis variables
specifies the variables to be analyzed. For each variable that you assign to this role, the task creates a one-way frequency table. You must assign at least one variable to this role.
Additional Roles
Frequency count
specifies the variable to use as the frequency count. When you assign a variable to this role, each observation in the table is assumed to represent n observations. In this example, n is the value of the frequency count for that row. You can assign only one variable to this role.
Group analysis by
specifies one or more variables to sort the table by. Analyses are performed on each group.

Setting Options

Option Name
Description
Plots
By default, plots are included in the results. Select the Show frequencies table check box to create the frequency and cumulative frequency plots. Select the Asymptotic test check box for the chi-square goodness-of-fit to create the deviation plot.
To suppress the plots from the results, select the Suppress plots check box.
Frequencies and Percentages
Show frequencies table
specifies whether to create the frequencies table.
Include percentages
creates a table that contains the frequencies and percentages of total frequencies for each value of the analysis variable.
Include cumulative frequencies and percentages
creates a table that contains the frequencies and cumulative frequencies for each value of the analysis variable.
Statistics
Binomial Proportion
Specify whether to perform an asymptotic test. For binomial proportions, specify a null hypothesis proportion and a confidence level.
Chi-square goodness-of-fit
Specify whether to perform an asymptotic test.
To compute the Monte Carlo estimates of the exact p-values instead of directly computing the exact p-values, select the Use Monte Carlo estimation check box. Monte Carlo estimation can be useful for large problems that require a great amount of time and memory for exact computations but for which asymptotic approximations might be insufficient.
Exact Computations Methods
Note: This section appears if you select the Exact test check box for the binomial proportion or chi-square goodness-of-fit statistics.
Limit computation time
specifies the time limit (in seconds) for the computation of each p-value for each crosstabulation table. The default is 300 seconds (or 5 minutes).
Missing Values
Include in frequency table
includes missing values in the frequency tables.
Include in percentages and statistics
includes the frequencies of missing values in binomial or chi-square tests and in the calculations of percentages.