Chapter 9, Problem 11CRP

In Problems 8-12, please use the following steps (i)-(v) for all hypothesis tests:

(i) What is the level of significance? State the null and alternate hypotheses.

(ii) Check Requirements What sampling distribution will you use? What assumptions are you making? What is the value of the sample test statistic?

(iii) Find (or estimate) the P-value. Sketch the sampling distribution and show the area corresponding to the P-value.

(iv) Based on your answers in parts (i)-(iii), will you reject or fail to reject the null hypothesis? Are the data statistically significant at level a?

(v) Interpret your conclusion in the context of the application.

Note: For degrees of freedom d.f. not in the Student’s t table, use the closet d.f. that is smaller. In some situation, this choice of d.f. may increase the P-value a small amount and thereby produce a slightly more "conservative” answer.

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

Write a brief essay in which you discuss using in formation 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 significance 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.

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 specified 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?