# A test of independence tests the null hypothesis, post navigation

For example, say a researcher wants to examine the relationship between gender male vs. Interpret Results If the sample findings are unlikely, given the null hypothesis, the researcher rejects the null hypothesis.

The Sampling Schemes For the sake of concreteness, suppose we're interested in comparing the proportions of high school freshmen and high school seniors falling into various driving categories — perhaps, those who don't drive at all, those who drive unsafely, and those who drive safely.

We randomly select freshmen and new deal dbq essay 2003 and then observe into which of the three driving categories each student falls: By the way, I think I might have mumbled something up above about the equivalence of the chi-square statistic for homogeneity and the chi-square statistic for independence.

In the population, two categorical variables are dependent. Here's the table of expected counts: In those cases you might want to turn to McNemar's test.

Typically, this involves comparing the P-value to the significance leveland rejecting the null hypothesis when the P-value is less than the significance level. Respondents were classified by gender male or female and by voting preference Republican, Democrat, or Independent.

This approach consists of four steps: