It is common to fit a model where a variable (or variables) has an effect on the expected mean. You may also want to fit a model where a variable…
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This sounds like it should be pretty easy. Let’s load the hsbdemo dataset and overlay histograms for males and female for the variable write. use https://stats.idre.ucla.edu/stat/data/hsbdemo, clear twoway (histogram write…
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Stata FAQ How do I specify types of missing values? When a data file has missing values, sometimes we may want to be able to distinguish between different types of…
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Sometimes the output of the list command can be clumsy, showing an entire observation with all of the variables wrapped across the screen. Sometimes you would like the data shown…
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The margins command introduced in Stata 11 provides an easy way to compute contrasts in analysis of variance designs. We will begin by loading the hsbanova dataset and running a…
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The margins command can be a very useful tool in understanding and interpreting interactions. We will illustrate the command in two examples using the hsbdemo dataset. use https://stats.idre.ucla.edu/stat/data/hsbdemo, clear Example…
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The anova and mixed commands present their results rather differently. The anova command displays a single test for each factor in the model including factors that have more than one…
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Little and Rubin (2002 p. 87) recommend a three step procedure for using multiple imputation with bootstrap standard errors: Generate bootstrap samples from the unimputed data; Impute missing values in…
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How can I perform multiple imputation on longitudinal data using ICE? Imputing longitudinal or panel data poses special problems. If  the data are in long form, each case has multiple…
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R2 and adjusted R2 are often used to assess the fit of OLS regression models. Below we show how to estimate the R2 and adjusted R2 using the user-written command…
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