FAQ: What are the differences between one-tailed and two-tailed tests? When you conduct a test of statistical significance, whether it is from a correlation, an ANOVA, a regression or some…
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Consider the three-way ANOVA, shown below, with a significant three-way interaction. There are 24 observations in this analysis. In this model a has two levels, b two levels and c…
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Suppose we would like to compare two raters using a kappa statistic but the raters have different range of scores. This situation most often presents itself where one of the…
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This page shows the survey setups for common public use data sets in various statistical packages, including SUDAAN, Stata and SAS. If you are using an earlier version of one…
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This page shows the survey setups for common public use data sets in various statistical packages, including SUDAAN 10.1, Stata 12.1 and SAS 9.3.  If you are using an earlier…
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How can I convert a Stata data file to a MLwiN data file? Can you suggest naming schemes for variables? How do I make a grand mean centered variable? How…
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These code fragments are examples that we are using to try and understand these techniques using Mplus.  We ask that you treat them as works in progress that explore these…
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These code fragments are examples that we are using to try and understand these techniques using Mplus.  We ask that you treat them as works in progress that explore these…
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These code fragments are examples that we are using to try and understand these techniques using Mplus.  We ask that you treat them as works in progress that explore these…
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These code fragments are examples that we are using to try and understand these techniques using Mplus.  We ask that you treat them as works in progress that explore these…
Read More