This page is just an extension of How can I do moderated mediation in Stata? to include a categorical moderator variables. We will call that page modmed. If you are…
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Note: The commands shown in this page are user-written Stata commands that must be downloaded.  To install the package of spatial analysis tools, type search spatgsa in the command window. …
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Preacher and Hayes (2008) show how to analyze models with multiple mediators in SPSS and SAS, how can I analyze multiple mediators in Stata? Here is the full citation: Preacher,…
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Consider the following mediation model run as a multiple group structural equation model (sem) with science as the final response variable, math as the independent variable and read as the…
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These data are from a longitudinal growth model with two level-1 predictors, time and time^2. There are two level-2 predictors of the random intercepts, x (a continuous predictor) and grp…
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NOTE: This page describes usage of an older version of the merge command (prior to Stata 11), which allowed multiple files to be merged in the same merge command.  The current version of merge…
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Please note: The following example is for illustrative purposes only. The data presented is not meant to recommend or encourage the estimation of random effects on categorical variables with very…
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Purpose: This page shows you how to conduct a likelihood ratio test and Wald test in Stata. For a more conceptual understanding, including an explanation of the score test, refer to …
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It is not uncommon to believe a variable x predicts a variable y differently over certain ranges of x.  In such instances, you may wish to fit a piecewise regression…
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This FAQ illustrates the nmissing and npresent commands which show you the number of missing, and number of non-missing values for your variables. The nmissing and npresent commands were written…
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