The COUNTREG Procedure
- Overview
- Getting Started
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Syntax
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DetailsSpecification of RegressorsMissing ValuesPoisson RegressionNegative Binomial RegressionZero-Inflated Count Regression OverviewZero-Inflated Poisson RegressionZero-Inflated Negative Binomial RegressionVariable SelectionComputational ResourcesNonlinear Optimization OptionsCovariance Matrix TypesDisplayed OutputOUTPUT OUT= Data SetOUTEST= Data SetODS Table Names
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Examples
- References
Variable Selection
Variable Selection
Variable selection uses either Akaike’s information criterion (AIC) or the Schwarz Bayesian criterion (SBC) and either a forward selection method or a backward elimination method.
Forward selection starts from a small subset of variables. In each step, the variable that gives the largest decrease in the value of the information criterion specified in the CRITER= option (AIC or SBC) is added. The process stops when the next candidate to be added does not reduce the value of the information criterion by more than the amount specified in the LSTOP= option in the MODEL statement.
Backward elimination starts from a larger subset of variables. In each step, one variable is dropped based on the information criterion chosen.