The Essentials of Statistics: A Tool for Social Research
4th Edition
ISBN: 9781305802698
Author: Joseph F. Healey
Publisher: Cengage Learning US
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Chapter 10, Problem 10.4P
a. Is there a relationship between these variables? Do cities with higher homicide rates have significantly higher handgun sales? Explain your results in a sentence or two, citing both the results of the chi square test and the patterns of the column percentages.
b. The table is constructed assuming that homicide rate is the independent variable (“higher homicide rates cause people to buy more guns”). Can you think of an argument that would make handgun sales the independent variable? Which is the more logical argument? Why?
| Volume of Handgun Sales | Homicide Rate | ||
| Low | High | Totals | |
| High | 8 | 5 | 13 |
| Low Totals |
|
|
|
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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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replicated twice. The design is shown in Table 3.
A222222222222233
Stir Rate
(RPM)
Ammonium
(%)
Table 3: Silver Powder Experiment from Exercise 13.23
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Density
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100
8
14.68
0.40
100
8
15.18
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8
15.12
0.42
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100
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
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8
12.62
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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
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(a) Write two regression models for predicting crack length, one for each level of the heat treatment method
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(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 10 Solutions
The Essentials of Statistics: A Tool for Social Research
Ch. 10 - The following four 22 tables, presented without...Ch. 10 - PS As mentioned in this chapter, many analysts...Ch. 10 - SW A local politician is concerned that a program...Ch. 10 - SOC A sample of 25 cities have been classified as...Ch. 10 - PA Is there a relationship between salary levels...Ch. 10 - CJ A local judge has been allowing some...Ch. 10 - SOC The state Department of Education has rated a...Ch. 10 - SOC A program of pet therapy has been running at a...Ch. 10 - SOC Is there a statistically significant...Ch. 10 - PS Is there a relationship between college class...
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