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 8.1, Problem 1E
A simple random sample of 40 items resulted in a sample
- a. What is the standard error of the mean, σx?
- b. At 95% confidence, what is the margin of error?
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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
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(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
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15.18
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8
15.12
0.42
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17.48
0.41
150
7.54
0.69
150
8
6.66
0.67
30
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8
12.46
0.52
30
150
8
12.62
0.36
100
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12.65
0.57
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-
+
++
Table 2: Crack Experiment for Exercise 2
A B C D Treatment Combination
(1)
Replicate
I II
7.037
6.376
14.707 15.219
|++++ 1
བྱ॰༤༠སྦྱོ སྦྱོཋཏྟཱུ
a
b
ab
11.635 12.089
17.273 17.815
с
ас
10.403 10.151
4.368 4.098
bc
abc
9.360 9.253
13.440 12.923
d
8.561 8.951
ad
16.867 17.052
bd
13.876 13.658
abd
19.824 19.639
cd
11.846 12.337
acd
6.125
5.904
bcd
11.190 10.935
abcd
15.653 15.053
Question 3
Continuation of Exercise 2. One of the variables in the experiment described in Exercise 2, heat treatment
method (C), is a categorical variable. Assume that the remaining factors are continuous.
(a) Write two regression models for predicting crack length, one for each level of the heat treatment method
variable. What differences, if any, do you notice in these two equations?
(b) Generate appropriate response surface contour plots for the two regression models in part (a).
(c) What set of conditions would you recommend for the factors A, B, and D if you use heat treatment method
C = +?
(d) Repeat…
Chapter 8 Solutions
Essentials Of Statistics For Business & Economics
Ch. 8.1 - A simple random sample of 40 items resulted in a...Ch. 8.1 - 2. A simple random sample of 50 items from a...Ch. 8.1 - A simple random sample of 60 items resulted in a...Ch. 8.1 - 4. A 95% confidence interval for a population mean...Ch. 8.1 - Data were collected on the amount spent by 64...Ch. 8.1 - Travel Taxes. In an attempt to assess total daily...Ch. 8.1 - Cost of Dog Ownership. Money reports that the...Ch. 8.1 - Studies show that massage therapy has a variety of...Ch. 8.1 - Cost to Repair Fire Damage. The mean cost to...Ch. 8.1 - 10. Costs are rising for all kinds of medical...
Ch. 8.2 - For a t distribution with 16 degrees of freedom,...Ch. 8.2 - Find the t value(s) for each of the following...Ch. 8.2 - The following sample data are from a normal...Ch. 8.2 - A simple random sample with n = 54 provided a...Ch. 8.2 - 15. Sales personnel for Skillings Distributors...Ch. 8.2 - Years to Bond Maturity. A sample containing years...Ch. 8.2 - Quality Ratings of Airports. The International Air...Ch. 8.2 - Unemployment in Older Workers. Older people often...Ch. 8.2 - Meal Cost in Hong Kong. The mean cost of a meal...Ch. 8.2 - Automobile Insurance Premiums. The average annual...Ch. 8.2 - Telemedicine. Health insurers are beginning to...Ch. 8.2 - Movie Ticket Sales. Marvel Studios motion picture...Ch. 8.3 - 23. How large a sample should be selected to...Ch. 8.3 - The range for a set of data is estimated to be 36....Ch. 8.3 - Refer to the Scheer Industries example in Section...Ch. 8.3 - Gasoline Prices. The U.S. Energy Information...Ch. 8.3 - Salaries of Business Graduates. Annual starting...Ch. 8.3 - 28. Many medical professionals believe that eating...Ch. 8.3 - 29. Customers arrive at a movie theater at the...Ch. 8.3 - Prob. 30ECh. 8.4 - A simple random sample of 400 individuals provides...Ch. 8.4 - A simple random sample of 800 elements generates a...Ch. 8.4 - In a survey, the planning value for the population...Ch. 8.4 - At 95% confidence, how large a sample should be...Ch. 8.4 - Health-Care Survey. In the spring of 2017, the...Ch. 8.4 - According to statistics reported on CNBC, a...Ch. 8.4 - Voter Sentiment. One of the questions Rasmussen...Ch. 8.4 - 38. According to Franchise business review, over...Ch. 8.4 - In 16% of all homes with a stay-at-home parent,...Ch. 8.4 - Prob. 40ECh. 8.4 - Driver’s License Rates. Fewer young people are...Ch. 8.4 - 42. A poll for the presidential campaign sampled...Ch. 8.4 - 43. The Pew Research Center Internet Project,...Ch. 8.5 - Federal Tax Return Errors. Suppose a sample of...Ch. 8.5 - Federal Government Employee Sick Hours. According...Ch. 8.5 - Web Browser Satisfaction. Internet users were...Ch. 8.5 - Speeding Drivers. In 2017, ABC News reported that...Ch. 8 - 44. A sample survey of 54 discount brokers showed...Ch. 8 - 45. A survey conducted by the American Automobile...Ch. 8 - 46. The 92 million Americans of age 50 and over...Ch. 8 - Healthy Sleep Duration. The Centers for Disease...Ch. 8 - The Health Care Cost Institute tracks health care...Ch. 8 - Obesity. Obesity is a risk factor for many health...Ch. 8 - Prob. 54SECh. 8 - 51. In developing patient appointment schedules, a...Ch. 8 - Prob. 56SECh. 8 - 53. The National Center for Education Statistics...Ch. 8 - A USA Today/CNN/Gallup survey of 369 working...Ch. 8 - Social Media Usage. The Pew Research Center has...Ch. 8 - Prob. 60SECh. 8 - The Centers for Disease Control reported the...Ch. 8 - A well-known bank credit card firm wishes to...Ch. 8 - Credit Card Ownership. Credit card ownership...Ch. 8 - 60. Although airline schedules and cost are...Ch. 8 - Driving Speeds. Huston Systems Private Limited...Ch. 8 - Prob. 66SECh. 8 - Prob. 67SECh. 8 - Prob. 68SECh. 8 - Young Professional Magazine Young Professional...Ch. 8 - Gulf Real Estate Properties Gulf Real Estate...Ch. 8 - Metropolitan Research, Inc.
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