Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card)
6th Edition
ISBN: 9780357191484
Author: David R. Anderson; Dennis J. Sweeney; Thomas A. Williams
Publisher: Cengage Learning US
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Textbook Question
Chapter 10.1, Problem 8E
Increases in Customer Satisfaction. Will improving customer service result in higher stock prices for the companies providing the better service? “When a company’s satisfaction score has improved over the prior year’s results and is above the national average (75.7), studies show its shares have a good chance of outperforming the broad stock market in the long run.” The following satisfaction scores of three companies for the 4th quarters of two previous years were obtained from the American Customer Satisfaction Index. Assume that the scores are based on a poll of 60 customers from each company. Because the polling has been done for several years, the standard deviation can be assumed to equal 6 points in each case.
- For Rite Aid, is the increase in the satisfaction score from year 1 to year 2 statistically significant? Use α = .05. What can you conclude?
- Can you conclude that the year 2 score for Rite Aid is above the national average of 75.7? Use α = .05.
- For Expedia, is the increase from year 1 to year 2 statistically significant? Use α = .05.
- When conducting a hypothesis test with the values given for the standard deviation,
sample size , and α, how large must the increase from year 1 to year 2 be for it to be statistically significant? - Use the result of part (d) to state whether the increase for J.C. Penney from year 1 to year 2 is statistically significant.
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Question 4
An article in Quality Progress (May 2011, pp. 42-48) describes the use of factorial experiments to improve a
silver powder production process. This product is used in conductive pastes to manufacture a wide variety of
products ranging from silicon wafers to elastic membrane switches. Powder density (g/cm²) and surface area
(cm/g) are the two critical characteristics of this product. The experiments involved three factors: reaction
temperature, ammonium percentage, stirring rate. Each of these factors had two levels, and the design was
replicated twice. The design is shown in Table 3.
A222222222222233
Stir Rate
(RPM)
Ammonium
(%)
Table 3: Silver Powder Experiment from Exercise 13.23
Temperature
(°C)
Density
Surface Area
100
8
14.68
0.40
100
8
15.18
0.43
30
100
8
15.12
0.42
30
100
17.48
0.41
150
7.54
0.69
150
8
6.66
0.67
30
150
8
12.46
0.52
30
150
8
12.62
0.36
100
40
10.95
0.58
100
40
17.68
0.43
30
100
40
12.65
0.57
30
100
40
15.96
0.54
150
40
8.03
0.68
150
40
8.84
0.75
30
150…
Chapter 10 Solutions
Modern Business Statistics with Microsoft Office Excel (with XLSTAT Education Edition Printed Access Card)
Ch. 10.1 - The following results come from two independent...Ch. 10.1 - 2. Consider the following hypothesis test.
The...Ch. 10.1 - 3. Consider the following hypothesis test.
The...Ch. 10.1 - 4. Condé Nast Traveler conducts an annual survey...Ch. 10.1 - 5. The USA Today reports that the average...Ch. 10.1 - Hotel Price Comparison. Suppose that you are...Ch. 10.1 - Consumer Reports uses a survey of readers to...Ch. 10.1 - Increases in Customer Satisfaction. Will improving...Ch. 10.2 - The following results are for independent random...Ch. 10.2 - Consider the following hypothesis test:
The...
Ch. 10.2 - Consider the following data for two independent...Ch. 10.2 - Prob. 12ECh. 10.2 - Annual Cost of College. The increasing annual cost...Ch. 10.2 - Are nursing salaries in Tampa, Florida, lower than...Ch. 10.2 - Hotel prices worldwide are projected to increase...Ch. 10.2 - Effect of Parents’ Education on Student SAT...Ch. 10.2 - Comparing Financial Consultant Ratings....Ch. 10.2 - Researchers at Purdue University and Wichita State...Ch. 10.3 - Consider the following hypothesis test.
The...Ch. 10.3 - The following data are from matched samples taken...Ch. 10.3 - Prob. 21ECh. 10.3 - The price per share of stock for a sample of 25...Ch. 10.3 - Credit Card Expenditures. Bank of America’s...Ch. 10.3 - Domestic Airfare. The Global Business Travel...Ch. 10.3 - Prob. 25ECh. 10.3 - PGA Tour Scores. Scores in the first and fourth...Ch. 10.3 - Price Comparison of Smoothie Blenders. A personal...Ch. 10.4 - Consider the following results for independent...Ch. 10.4 - Prob. 29ECh. 10.4 - Corporate Hiring Outlook. A Businessweek/Harris...Ch. 10.4 - Impact of Pinterest on Purchase Decisions. Forbes...Ch. 10.4 - Mislabeled Fish. Researchers with Oceana, a group...Ch. 10.4 - Minnesota had the highest turnout rate of any...Ch. 10.4 - Oil wells are expensive to drill, and dry wells...Ch. 10.4 - In a test of the quality of two television...Ch. 10.4 - Winter visitors are extremely important to the...Ch. 10.4 - Prob. 37ECh. 10 - Prob. 38SECh. 10 - SUV Lease Payments. Statista reports that the...Ch. 10 - Prob. 40SECh. 10 - Kitchen Versus Bedroom Remodeling Costs. The...Ch. 10 - Effect of Siblings on SAT Scores. In Born...Ch. 10 - Country Financial, a financial services company,...Ch. 10 - Prob. 44SECh. 10 - Prob. 45SECh. 10 - News Access Via Computer. The American Press...Ch. 10 - For the week ended January 15, 2009, the bullish...
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