Randomized block type designs are relatively common in certain fields. Balanced randomized designs can be analyzed using traditional anova and regression methods but unbalanced designs require the use of maximum…
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Beginning in Stata 12 you can read Excel (.xls and .xlsx) files directly using the import excel command.  The sheet() option allows us top specify from which sheet of the spreadsheet…
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Consider the file below that contains four variables, make, mpg, weight, and price. The file looks like what is shown below (the variable names are indeed the first line of…
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Two of the more common measures of effect size for regression analysis are eta2 and partial eta2. Eta2 is the proportion of the total variance that is attributed to an…
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String processing is fairly easy in Stata because of the many built-in string functions. Among these string functions are three functions that are related to regular expressions, regexm for matching,…
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Credits This page was developed and written by Karla Lindquist, Senior Statistician in the Division of Geriatrics at UCSF. We are very grateful to Karla for taking the time to…
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Testing simple effects in repeated measures models that have both between-subjects and within-subjects effects can be tricky. We will look at two different estimation approaches, linear mixed model and anova….
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In addition to the output in the shown in the results window, many of Stata’s commands store information about the command and it’s results in memory. This allows the user,…
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xtreg with its various options performs regression analysis on panel datasets. In this FAQ we will try to explain the differences between xtreg, re and xtreg, fe with an example…
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In Stata it is very easy to get the area under the ROC curve following either logit or logistic by using the lroc command. However, with lroc you cannot compare…
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