[EMAIL PROTECTED] (mac55) wrote in news:[EMAIL PROTECTED]:
> A simple question...... > > If you are comparing binary data from two groups with underlying > populations that are normal.....I assume you can use a two sample Z > test for binomial proportions or a chi squared test on a 2x2 > contingency table. > > What happens if the underlying populations aren't normal? I know > the Z test is out. Can you still employ the chi squared distribution. > If not, what non-parametric test could you use? Nothing in the logic of either test requires the assumption that the data be derived by dichotomizing a normal continuous variable. The Z test only requires that the number of cases be large enough that the normal approximation to the binomial is decent. . . ================================================================= Instructions for joining and leaving this list, remarks about the problem of INAPPROPRIATE MESSAGES, and archives are available at: . http://jse.stat.ncsu.edu/ . =================================================================
