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needing help with statistics homework

HOMEWORK 6 20 points Chapter 7. Confidence Intervals. Submit all work done by hand or using Excel to recelve ful credit. 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 ikellhood of rejecting the nul hypothesis? Explain. Use the SEM formula from the lecture notes to complete the following question. Make sure you submit all work done (e.g. typed or a clear picture of your work) in order to receive full credit. 4. How satisfied are hotel managers with the computer systems their hotels use? A survey was sent to 400 managers in hotels of size 200 to 500 rooms in Chicago and Detroit. In all, 100 managers returned the survey Two questions concemed 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 popuation 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 trainng, the mean response was 4 398 Assuming the sample SD is 1.75 find the 99% confidence interval for the managers sampled e. Prowde an interpretaton of your answer obtained for part D NEXT PAGE 5. 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 samplod 24 oigarcttoa. The nicotinc level for caoh of thc sampled oigarcttca ia given bclow. Nicotine ma | 1.8 Nicotine mg 1.6 1.9 | Nou 19 1.2 1.2 1.0 2.0 1.7 2.0 2.3 2.0 1.8 4 0.9 2.4 a. Use Excel to obtain the sample mean and sample SD. Construct the 95 % confidence interval. Enter the data into one, single column. 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 women?

Answer 1

Answer:

As per HOMEWORKLIB RULES i answer only 2 questions....