255-2013: MIXED_FIT: A SAS® Macro to Assess Model Fit and Adequacy for Two-Level Linear Models
نویسندگان
چکیده
When estimating multilevel models it is important for researchers to make sure their models fit their data. However, examining model fit can be quite cumbersome. We have developed the macro MIXED_FIT to help researchers assess model fit in a simple yet comprehensive way. Specifically, this paper provides a SAS macro that incorporates changes in model fit statistics [i.e., -2 log likelihood (-2LL), AIC, and BIC] as well as changes in pseudo-R 2 . By utilizing data from PROC MIXED ODS tables, the macro produces a comprehensive table of changes in model fit measures and allows SAS users to examine model fit in both nested and non-nested models both in terms of statistical and practical significance without having to calculate these values by hand.
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