A variable in %tm format is a numeric variable which is the number of months elapsed since January 1960. One may want to extract the month or the year component…
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Method Note: We are unsure whether this method should be used to estimate effect sizes for predictors that vary somewhat or completely at the between-cluster level (i.e., vary at level…
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  Installing Stata is fairly straight forward.  For the most part, accepting the default settings if fine, but you may wish to change the default directory that Stata uses when it opens….
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Can’t find your question? Try checking our General FAQ page. Transferring data to/from Stata How can I convert files among SAS, SPSS and Stata? How can I read data from multiple…
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We recently received a question asking why the results from the same model specified as anova versus a regression would not agree. The model in question had both categorical and continuous predictors. This…
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The anovalator command refers to a mythical program that displays the results of an estimation command in an anova-like manner, that is, separate multidegree of freedom tests for main effects,…
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Large datasets sometimes come as a series of smaller datasets each containing information from a subset of cases. For example, one dataset for each U.S. State, or one dataset per…
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To analyze a factorial anova you would use the anova command. The anova command does not have a check for homogeneity of variance. However, the oneway command automatically performs a…
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Sometimes your research may predict that the size of a regression coefficient should be bigger for one group than for another. For example, you might believe that the regression coefficient…
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When modeling a count variable, there are several available models to choose from. Stata supports Poisson, negative binomial, zero-inflated Poisson, zero-inflated negative binomial models, zero-truncated Poisson, and zero-truncated negative binomial…
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