4 points Chapter 7. Answer the following questions on a separate piece of paper. 1. (a) What is a confidence interval? (b) What do confidence intervals allow researchers to conclude? Explain your answers. 2. What factors affect the size of a confidence interval? Explain your answer. 3. (a) What does the p-value indicate? Explain. (b) What are the typical values of the p-value? (c) What effect will reducing a p-value from .05 to .01 have on likelihood of rejecting the null hypothesis? Explain. 4. How satisfied are hotel managers with the computer systems their hotels use? A survey was sent to 100 managers in hotels of size 200 to 500 rooms in Chicago and Detroit. In all, 135 managers returned the survey. Two questions concerned their degree of satisfaction with the ease of use of their computer systems and with the level computer training they had received. The managers responded using a seven-point scale, with 1 meaning “not satisfied,” and 4 meaning “moderately satisfied,” and 7 meaning “very satisfied.” a. What do you think is the population for this study? What are the major shortcomings in the obtained data? b. The mean response for satisfaction with ease of use was 5.396. Find the 95% confidence interval for the managers sampled. (Assume the sample SD = 1.75.) c. Provide an interpretation for your answer in part B. d. For satisfaction with training, the mean response was 4.398. Assuming the sample SD is 1.75, find the 99% confidence interval for the managers sampled. e. Provide an interpretation of your answer obtained for part D. NEXT PAGE Æ5. A health advocacy group conducted a study to determine if the nicotine content of a particular brand of cigarettes was equal to the advertised amount. The cigarette brand advertised that the average nicotine content per cigarette was 1.4 milligrams. The advocacy group randomly sampled 24 cigarettes. The nicotine level for each of the sampled cigarettes is given below. Nicotine mg. Nicotine mg.1.8 1.91.1 1.61.2 1.91.2 1.91.0 2.02.0 1.61.7 1.12.0 1.82.3 1.91.4 1.40.9 1.82.4 1.5 a. Use Excel to obtain the sample mean and sample SD. Construct the 95 % confidence interval. b. Provide an interpretation of the confidence interval from part A. c. Does the obtained confidence interval contain the average nicotine level per cigarette suggested by the cigarette maker? Explain what this means. 6. A New York Times poll on women’s issues interviewed 1025 women and 472 men randomly selected from the United States, excluding Alaska and Hawaii. The poll announced a margin of error of ±3 percentage points for 95% confidence in conclusions about women. The margin of error for results concerning men was ±4 percentage points. Why is this larger than the margin of error obtained for