1. Chi-square for tables Homogeneity and independence

2. For tables—starting at 2 X 2, there are two kinds of test---with the exact same mechanics— –Independence—is there an influence? orHo: There is no association between gender and political party (in other words, women and men would join parties at the same rate) or (gender and political party are independent) Ha: There is an association between gender and political party. (in other words, they are different.) or (gender and political party are dependent.)

3. Homogeneity vs. Independence Homogeneity– sameness Example: –Ho: Political affiliation for women is the same as it was 60 years ago. –Ha: political affiliation for women is different than it was 60 years ago.

4. The mechanics GOPDEM 19594060 200950 Find the expected value first---the expected values assume that Ho is true, in this case that women have the same political party preference as 50 years ago. You do this by Row total X column total / table total

5. Women and politics GOPDEM 19594555 20094555 Here are the expected cells—you can do this by hand or on the calculator. Then the Chi-square sum will be: (40-45)^2/45 + (50-45)^2/45 + (60-55)^2/55 + (50-55)^2/55 = a chi square sum of 2.0202 with degree of freedom of 1 (r-1)(c-1) P-value of.1552