A multiple choice question that gives four different ways of calculating the z-test statistic for a test for a proportion.

A multiple choice question where students have to identify the possible ways of increasing the power of a test.

On the free response, you should have two questions. One question asking students to do a significance test for a proportion, and one question asking students to do a significance test. Use old AP questions.

Consider having a follow up question part (b) for each significance test. Here are some options for your follow-up question:

• Given your conclusion in part (a), which kind of mistake—a Type I error or a Type II error—could you have made? Explain what this mistake would mean in context.

• Why do we check the (random, 10%, Large Counts) condition?

• A simulation based estimate of the P-value (seriously 2009B #5 is the best question ever….if your students do well on this question, then you did a great job teaching Chapter 9!)

• Give students the confidence interval for the data in part (a) and ask them to explain why the confidence interval leads to the same conclusion as the significance test.

• Ask students if the significance test reveals a causal relationship. If the data comes from an observational study, then we cannot infer causation.

• The power of this test to detect the alternative (Ha) is _______. Interpret this value.