The SURVEYLOGISTIC Procedure
- Overview
- Getting Started
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Syntax
PROC SURVEYLOGISTIC Statement BY Statement CLASS Statement CLUSTER Statement CONTRAST Statement DOMAIN Statement EFFECT Statement ESTIMATE Statement FREQ Statement LSMEANS Statement LSMESTIMATE Statement MODEL Statement OUTPUT Statement REPWEIGHTS Statement SLICE Statement STORE Statement STRATA Statement TEST Statement UNITS Statement WEIGHT Statement -
Details
Missing Values Model Specification Model Fitting Survey Design Information Logistic Regression Models and Parameters Variance Estimation Domain Analysis Hypothesis Testing and Estimation Linear Predictor, Predicted Probability, and Confidence Limits Output Data Sets Displayed Output ODS Table Names ODS Graphics
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Examples
- References
Response Variable Options
You specify the following options by enclosing them in parentheses after the response variable:
- DESCENDING
- DESC
reverses the order of response categories. If both the DESCENDING and the ORDER= options are specified, PROC SURVEYLOGISTIC orders the response categories according to the ORDER= option and then reverses that order. See the section Response Level Ordering for more detail.
- EVENT=’category’ | keyword
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specifies the event category for the binary response model. PROC SURVEYLOGISTIC models the probability of the event category. The EVENT= option has no effect when there are more than two response categories. You can specify the value (formatted if a format is applied) of the event category in quotes or you can specify one of the following keywords. The default is EVENT=FIRST.
- FIRST
designates the first ordered category as the event
- LAST
designates the last ordered category as the event
One of the most common sets of response levels is {0,1}, with 1 representing the event for which the probability is to be modeled. Consider the example where Y takes the values 1 and 0 for event and nonevent, respectively, and Exposure is the explanatory variable. To specify the value 1 as the event category, use the following MODEL statement:
model Y(event='1') = Exposure;
- ORDER=DATA | FORMATTED | FREQ | INTERNAL
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specifies the sorting order for the levels of the response variable. By default, ORDER=INTERNAL. For ORDER=FORMATTED and ORDER=INTERNAL, the sort order is machine-dependent.
When the default ORDER=FORMATTED is in effect for numeric variables for which you have supplied no explicit format,
Value of ORDER=
Levels Sorted By
DATA
Order of appearance in the input data set
FORMATTED
External formatted value, except for numeric
variables with no explicit format, which are
sorted by their unformatted (internal) value
FREQ
Descending frequency count; levels with the
most observations come first in the order
INTERNAL
Unformatted value
For more information about sorting order, see the chapter on the SORT procedure in the Base SAS Procedures Guide and the discussion of BY-group processing in SAS Language Reference: Concepts.
- REFERENCE=’category’ | keyword
- REF=’category’ | keyword
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specifies the reference category for the generalized logit model and the binary response model. For the generalized logit model, each nonreference category is contrasted with the reference category. For the binary response model, specifying one response category as the reference is the same as specifying the other response category as the event category. You can specify the value (formatted if a format is applied) of the reference category in quotes or you can specify one of the following keywords. The default is REF=LAST.
- FIRST
designates the first ordered category as the reference
- LAST
designates the last ordered category as the reference