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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This page was created to show various ways that Stata can analyze clustered data. The intent is to show how the various cluster approaches relate to one another. It is…
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There are two ways in which you can plot ANOVA cell means: anovaplot — user written program (search anovaplot) or enter a sequence of Stata commands from the command line….
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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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Sometimes your research may predict that the size of a regression coefficient may vary across groups. For example, you might believe that the regression coefficient of height predicting weight would…
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Multiple regression models often contain interaction terms. This FAQ page covers the situation in which there are two moderator variables which jointly influence the regression of the dependent variable on…
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First off, let’s start with what a significant continuous by continuous interaction means. It means that the slope of one continuous variable on the response variable changes as the values…
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Stata does not have a built-in contrast command; however, ATS has developed a program that will do ANOVA contrasts. You can download the program anovacontrast.ado by typing search anovacontrast (see…
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Everything? No, that’s a gross exaggeration. If you want to know everything about contrasts you will need read several other sources in addition to this page. Here are our suggestions:…
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