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Joyful mood is a meritorious deed that cheers up people around you like the showering of cool spring breeze. . Categorical Data Analysis. Chapter 6: Building Logistic Regression Models. Model Selection. Stepwise/backward/forward selection SAS PROC LOGISTIC AIC criterion:
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Joyful mood is a meritorious deed that cheers up people around you like the showering of cool spring breeze.
Categorical Data Analysis Chapter 6: Building Logistic Regression Models
Model Selection • Stepwise/backward/forward selection SAS PROC LOGISTIC • AIC criterion: AIC = -2(max. log likelihood - # of parameters) The smaller the AIC is, the better the model is
Example: Crab data • Visit Table 6.2 (p. 215) • Model symbols • Backward elimination (models 1-7) • AIC values • More advanced model selection (model 8) • SAS example code: crab.sas
Model Diagnostics • Assessment of the overall goodness of fit: Deviance measures the amount of loss of information • Residuals: Identify the lack of fit cells