Intro Stats
4th Edition
ISBN: 9780321825278
Author: Richard D. De Veaux, Paul F. Velleman, David E. Bock
Publisher: PEARSON
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Textbook Question
Chapter 6, Problem 3E
Bookstore sales Consider the following data from a small bookstore:
| Number of Sales People Working | Sales (in $1000) |
| 2 | 10 |
| 3 | 11 |
| 7 | 13 |
| 9 | 14 |
| 10 | 18 |
| 10 | 20 |
| 12 | 20 |
| 15 | 22 |
| 16 | 22 |
| 20 | 26 |
| x = 10.4 SD(x) = 5.64 |
y = 17.6 SD(y) = 5.34 |
- a) Prepare a
scatterplot of Sales against Number of sales people working. - b) What can you say about the direction of the association?
- c) What can you say about the form of the relationship?
- d) What can you say about the strength of the relationship?
- e) Does the scatterplot show any outliers?
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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
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replicated twice. The design is shown in Table 3.
A222222222222233
Stir Rate
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Ammonium
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Table 3: Silver Powder Experiment from Exercise 13.23
Temperature
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Density
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100
8
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100
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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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(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 6 Solutions
Intro Stats
Ch. 6.2 - Your statistics instructor tells you that the...Ch. 6.2 - Your statistics instructor tells you that the...Ch. 6.2 - Your statistics instructor tells you that the...Ch. 6.2 - Prob. 4JCCh. 6.2 - Prob. 5JCCh. 6 - Association Suppose you were to collect data for...Ch. 6 - Association II Suppose you were to collect data...Ch. 6 - Bookstore sales Consider the following data from a...Ch. 6 - Prob. 4ECh. 6 - Prob. 5E
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