Note that the output above said (obs=69). When you use correlate with variables with missing data.) correlate price mpg weight rep78 (obs=69) In the correlation even though it is not continuous to illustrate what happens Let’s look at the correlations among price mpg weight and rep78. We can use the correlate command to get theĬorrelations among variables. tabulate rep78 foreign, chi2 exact | foreign In such cases when you have empty cells, or cells with small frequencies, you can request Fisher’s exact test with the

The chi-square is not really valid when you have empty cells. We can use theĬhi2 option to request a chi-square test of independence as well as the crosstab. We may want to ask whether these variables are independent. Let’s compare the repair rating ( rep78) of the foreign and domestic cars. Let’s do a t-test comparing the miles per gallon ( mpg) Let’s use theĭata file that we will use for our examples. This module will give a brief overview of some common statistical tests in Stata. Version info: Code for this page was tested in Stata 12.

Pwcorr stata 15 vs stata 13