Essentials Of Statistics For Business & Economics
9th Edition
ISBN: 9780357045435
Author: David R. Anderson, Dennis J. Sweeney, Thomas A. Williams, Jeffrey D. Camm, James J. Cochran
Publisher: South-Western College Pub
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Textbook Question
Chapter 14.6, Problem 36E
In exercise 7, the data on y = annual sales ($ 1000s) for new customer accounts and x = number of years of experience for a sample of 10 salespersons provided the estimated regression equation ŷ = 80 + 4x. For these data
- a. Develop a 95% confidence interval for the
mean annual sales for all salespersons with nine years of experience. - b. The company is considering hiring Tom Smart, a salesperson with nine years of experience. Develop a 95% prediction interval of annual sales for Tom Smart.
- c. Discuss the differences in your answers to parts (a) and (b).
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In a study of possible correlation between the height in cm (X) and the weight in kg (Y) of chimpanzees, a sample of 40 animals produces a correlation coefficient of r=0.813 and a regression line with equation Y=0.34X+19.5. What is the expected weight of a chimpanzee that is 157 cm tall? Round off final answer to 2 decimal places.
The data on y = annual sales ($1,000s) for new customer accounts and x = number of years of experience for a sample of 10 salespersons provided the estimated regression equation
ŷ = 80 + 4x. For these data, x = 7, Σ(xi − x)2 = 142, and s = 4.6098.
(a)Develop a 95% confidence interval for the mean annual sales (in thousands of dollars) for all salespersons with seven years of experience. (Round your answers to two decimal places.)
$______ thousand to $_____thousand
(b)The company is considering hiring Tom Smart, a salesperson with seven years of experience. Develop a 95% prediction interval of annual sales (in thousands of dollars) for Tom Smart. (Round your answers to two decimal places.)
$_______ thousand to $_______ thousand
The data on y = annual sales ($1,000s) for new customer accounts and x = number of years of experience for a sample of 10 salespersons provided the estimated regression equation
ŷ = 80 + 4x.
For these data,
x = 7,
Σ(xi − x)2 = 142,
and
s = 4.6098.
(a)
Develop a 95% confidence interval for the mean annual sales (in thousands of dollars) for all salespersons with twelve years of experience. (Round your answers to two decimal places.)
$ thousand to $ thousand
(b)
The company is considering hiring Tom Smart, a salesperson with twelve years of experience. Develop a 95% prediction interval of annual sales (in thousands of dollars) for Tom Smart. (Round your answers to two decimal places.)
$ thousand to $ thousand
Chapter 14 Solutions
Essentials Of Statistics For Business & Economics
Ch. 14.2 - Given are five observations for two variables, x...Ch. 14.2 - Given are five observations for two variables, x...Ch. 14.2 - Given are five observations collected in a...Ch. 14.2 - Retail and Trade: Female Managers. The following...Ch. 14.2 - Production Line Speed and Quality Control. Brawdy...Ch. 14.2 - The National Football League (NFL) records a...Ch. 14.2 - Sales Experience and Performance. A sales manager...Ch. 14.2 - Broker Satisfaction. The American Association of...Ch. 14.2 - Estimating Landscaping Expenditures. David’s...Ch. 14.2 - Age and the Price of Wine. For a particular red...
Ch. 14.2 - Laptop Ratings. To help consumers in purchasing a...Ch. 14.2 - Stock Beta. In June of 2016, Yahoo Finance...Ch. 14.2 - Auditing Itemized Tax Deductions. To the Internal...Ch. 14.2 - Distance and Absenteeism. A large city hospital...Ch. 14.3 - 15. The data from exercise 1...Ch. 14.3 - Prob. 16ECh. 14.3 - The data from exercise 3 follow.
The estimated...Ch. 14.3 - Price and Quality of Headphones. The following...Ch. 14.3 - Prob. 19ECh. 14.3 - Price and Weight of Bicycles. Bicycling, the...Ch. 14.3 - Cost Estimation. An important application of...Ch. 14.3 - Prob. 22ECh. 14.5 - The data from exercise 1 follow.
Compute the mean...Ch. 14.5 - The data from exercise 2 follow.
Compute the mean...Ch. 14.5 - The data from exercise 3 follow.
What is the...Ch. 14.5 - Headphones Conclusion. In exercise 18, the data on...Ch. 14.5 - College CPA and Salary. Do students with higher...Ch. 14.5 - Broker Satisfaction Conclusion. In exercise 8,...Ch. 14.5 - Cost Estimation Conclusion. Refer to exercise 21,...Ch. 14.5 - Significance of Fleet Size on Rental Car Revenue....Ch. 14.5 - Significance of Racing Bike Weight on Price. In...Ch. 14.6 - The data from exercise 1 follow. xi 1 2 3 4 5 yi 3...Ch. 14.6 - Prob. 33ECh. 14.6 - 34. The data from exercise 3...Ch. 14.6 - Restaurant Lines. Many small restaurants in...Ch. 14.6 - 36. In exercise 7, the data on y = annual sales ($...Ch. 14.6 - In exercise 13, data were given on the adjusted...Ch. 14.6 - Prob. 38ECh. 14.6 - Entertainment Spend. The Wall Street Journal asked...Ch. 14.7 - Apartment Selling Price. The commercial division...Ch. 14.7 - Computer Maintenance. Following is a portion of...Ch. 14.7 - Annual Sales and Salesforce. A regression model...Ch. 14.7 - Estimating Setup Time. Sherry is a production...Ch. 14.7 - Auto Racing Helmet. Automobile racing,...Ch. 14.8 - Given are data for two variables, x and y. a....Ch. 14.8 - Prob. 46ECh. 14.8 - Restaurant Advertising and Revenue. Data on...Ch. 14.8 - Experience and Sales. Refer to exercise 7, where...Ch. 14.8 - Buy Versus Rent. Occasionally, it has been the...Ch. 14.9 - Consider the following data for two variables, x...Ch. 14.9 - Consider the following data for two variables, x...Ch. 14.9 - Predicting Charity Expenses. Charity Navigator is...Ch. 14.9 - Supermarket Checkout Lines. Retail chain Kroger...Ch. 14.9 - Valuation of a Major League Baseball Team. The...Ch. 14 - 55. Does a high value of r2 imply that two...Ch. 14 - Prob. 56SECh. 14 - What is the purpose of testing whether 1 = 0? If...Ch. 14 - Stock Market Performance. The Dow Jones Industrial...Ch. 14 - Home Sire and Price. Is the number of square feet...Ch. 14 - Online Education. One of the biggest changes in...Ch. 14 - Machine Maintenance. Jensen Tire & Auto is in the...Ch. 14 - Production Rate and Quality Control. In a...Ch. 14 - Absenteeism and Location. A sociologist was hired...Ch. 14 - Bus Maintenance. The regional transit authority...Ch. 14 - Studying and Grades. A marketing professor at...Ch. 14 - Market Beta. Market betas for individual stocks...Ch. 14 - Income and Percent Audited. The Transactional...Ch. 14 - Used Car Mileage and Price. The Toyota Camry is...Ch. 14 - One measure of the risk or volatility of an...Ch. 14 - As part of a study on transportation safety, the...Ch. 14 - Consumer Reports tested 166 different...Ch. 14 - When trying to decide what car to buy, real value...Ch. 14 - Buckeye Creek Amusement Park is open from the...
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