Essay and Project In Chapters 8 and 9 you studied estimation and hypothesis testing.

(a) Write a brief essay in which you discuss using information from samples to infer information about populations. Be sure to include methods of estimation and hypothesis testing in your discussion.

What two sampling distributions are used in estimation and hypothesis testing of population means and proportions? What are the criteria for determining the appropriate sampling distribution? What is the level of signifi cance of a test? What is the P-value? How is the P-value related to the alternate hypothesis? How is the null hypothesis related to the sample test statistic?

Explain.

(b) Suppose you want to study the length of time devoted to commercial breaks for two different types of television programs. Identify the types of programs you want to study (e.g., sitcoms, sports events, movies, news, children’s programs, etc.). Write a brief outline for your study. Discuss how to obtain random samples. How large should the sample be for a specifi ed margin of error? Describe the protocol you will follow to measure the times of the commercial breaks.

Determine whether you are going to compare the average time devoted to commercials or the proportion of time devoted to commercials. What assumptions will you make regarding population distributions? What graphics might be appropriate?

What methods of estimation will you use?

What methods of testing will you use?