1. * Chapter 8 – we were estimating with confidence about a population * Chapter 9 – we were testing a claim about a population * Chapter 10 – we are comparing two populations

2. Unit 10: Comparing Two Populations or Groups

5. * As part of the Pew Internet Project, researchers conducted two surveys in late 2009. The first survey asked a random sample of 800 US teens about their use of social media. A second survey posed similar questions to a random sample of 2253 US adults. In these two studies, 73% of teens and 47% of adults said they use social media. Use these results to construct and interpret a 95% confidence interval for the difference between the proportion of all US teens and adults who use social media. * State:

6. * Plan: * Do: * Conclude:

8. * Plan: * Do: * Conclude:

9. * High levels of cholesterol in the blood are associated with higher risk of heart attacks. Will using a drug to lower blood cholesterol reduce heart attacks? The volunteer subjects were assigned at random to one of two treatments: 2051 men took the drug gemfibrozil and a control group of 2030 men took a placebo. During the next 5 years, 56 men in the gemfibrozil group and 84 men in the control group had heart attacks. Is the apparent benefit of gemfibrozil statistically significant? * State:

10. * Plan: * Do: * Conclude:

11. * On the AP test there will be a formula that looks a little different…all they did was factor!

13. a) b) c)

14. * Pg. 621 (7-10, 15 do the test, 22, 24, 27-32)