The examples below use Stata 8.  If you are using Stata version 9, please see this page. This example is taken from Levy and Lemeshow’s Sampling of Populations. page 351…
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Collinearity is a property of predictor variables and in OLS regression can easily be checked using the estat vif command after regress or by the user-written command, collin (see How can…
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There is no svy: ttest command in Stata; however, svy: mean is an estimation command and allows for the use of both the test and lincom post-estimation commands. It is…
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The tabulate command is great for 2-way cross tabulations. But how do you do 3-way, 4-way, 5-way of more cross tabulations? The answer is to use the table command with…
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In a oneway analysis of variance (ANOVA), the alternative hypothesis is that the means across the levels of a factor variable are not equal. In the situation where the factor…
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Stata has added a maximum likelihood tetrachoric command to Stata 9.2. The matrix of tetrachoric correlations is saved in r(Rho) for use pic pcamat or factormat. If you need polychoric…
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First off, let’s start with what a significant three-way interaction means. It means that there is a two-way interaction that varies across levels of a third variable. Say, for example,…
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First off, let’s start with what a significant three-way interaction means. It means that there is a two-way interaction that varies across levels of a third variable. Say, for example,…
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First off, let’s start with what a significant three-way interaction means. It means that there is a two-way interaction that varies across levels of a third variable. Say, for example,…
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Let’s begin with with what a significant three-way interaction means. It means that there is a two-way interaction that varies across levels of a third variable. Say, for example, that…
Read More