OptinMon

Today we see how to set up multiple graphs on the same page. We use the syntax  par(mfrow=(A,B)) (more…)

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One of those “rules” about statistics you often hear is that you can’t interpret a main effect in the presence of an interaction.

Stats professors seem particularly good at drilling this into students’ brains.

Unfortunately, it’s not true.

At least not always. (more…)

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You may have heard of McNemar tests as a repeated measures version of a chi-square test of independence. This is basically true, and I wanted to show you how these two tests differ and what exactly, each one is testing.

First of all, although Chi-Square tests can be used for larger tables, McNemar tests can only be used for a 2×2 table.  So we’re going to restrict the comparison to 2×2 tables. (more…)

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For my first assignment using Stata, I spent four or five hours trying to present my output in a “professional” form. The most creative method I heard about in class the next day was to copy the contents into Excel, create page breaks, and then copy into Word.

SPSS makes it so easy to copy tables and graphs into another document. Why can’t Stata be easy?

Anyone who has used Stata has gone through this and many of you still are. No worries, help is on the way! (more…)

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We’ve already discussed using macros in Stata to simplify and shorten code.

Another great tool in your coding tool belt is loops. Loops allow you to run the same command for several variables at one time without having to write separate code for each variable.

This discussion could go on for pages and pages because there is much you can do with a loop. (more…)

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We finished the last article about Stata with the confusing coding of:

I admit it looks like a foreign language.  Let me explain how simple it is to understand. (more…)

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