Statistics, Books a la Carte Edition Plus MyLab Statistics with Pearson eText -- Access Card Package (4th Edition)
4th Edition
ISBN: 9780134435855
Author: Alan Agresti, Christine A. Franklin, Bernhard Klingenberg
Publisher: PEARSON
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Textbook Question
Chapter 8, Problem 81CP
Fuel efficiency The government website fueleconomy.gov has data on thousands of cars regarding their fuel efficiency. A random sample from this website of SUVs manufactured between 2012 and 2015 gives the following data on the combined (city and highway) miles per gallon (mpg):
26, 23, 21,23, 19, 29,15, 26, 19, 26.
- a. Construct an appropriate plot (or plots) to check the distributional assumption for computing a t interval for the
mean mpg for SUVs. Comment briefly. - b. Find and interpret a 95% confidence interval for the mean mpg for SUVs manufactured between 2012 and 2015.
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Question 4
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A222222222222233
Stir Rate
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Ammonium
(%)
Table 3: Silver Powder Experiment from Exercise 13.23
Temperature
(°C)
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Surface Area
100
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14.68
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15.12
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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).
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(d) Repeat…
Question 2
A nickel-titanium alloy is used to make components for jet turbine aircraft engines. Cracking is a potentially
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data are shown in Table 2.
1
(a) Estimate the factor effects. Which factor effects appear to be large?
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(c) Write down a regression model that can be used to predict crack length as a function of the significant
main effects and interactions you have identified in part (b).
(d) Analyze the residuals from this experiment.
(e) Is there an…
Chapter 8 Solutions
Statistics, Books a la Carte Edition Plus MyLab Statistics with Pearson eText -- Access Card Package (4th Edition)
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