Mathematical Statistics with Applications
7th Edition
ISBN: 9780495110811
Author: Dennis Wackerly, William Mendenhall, Richard L. Scheaffer
Publisher: Cengage Learning
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Chapter 12.3, Problem 13E
To determine
Explain whether matched-pairs design or independent samples procedure is needed to compare the mean plaque buildup for the two different times.
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A deficiency of the trace element selenium in the diet can negatively impact growth, immunity, muscle and neuromuscular function, and fertility. The introduction of selenium supplements to dairy cows is justified when pastures have low selenium levels. Authors of a research paper supplied the following data on milk selenium concentration (mg/L) for a sample of cows given a selenium supplement (the treatment group) and a control sample given no supplement, both initially and after a 9-day period.
Initial Measurement
Treatment
Control
11.4
9.1
9.6
8.7
10.1
9.7
8.5
10.8
10.2
10.9
10.6
10.6
11.9
10.1
9.9
12.3
10.7
8.8
10.2
10.4
10.3
10.9
11.4
10.4
9.3
11.6
10.6
10.9
10.9
8.3
After 9 Days
Treatment
Control
138.3
9.2
104
8.9
96.4
8.9
89
10.1
88
9.6
103.8
8.6
147.3
10.4
97.1
12.4
172.6
9.2
146.3
9.5
99
8.4
122.3
8.8
103
12.5
117.8
9.1
121.5
93
(a)
Use the given data for the treatment group to determine if…
A deficiency of the trace element selenium in the diet can negatively impact growth, immunity, muscle and neuromuscular function, and fertility. The introduction of selenium supplements to dairy cows is justified when pastures have low selenium levels. Authors of a research paper supplied the following data on milk selenium concentration (mg/L) for a sample of cows given a selenium supplement (the treatment group) and a control sample given no supplement, both initially and after a 9-day period.
Initial Measurement
Treatment
Control
11.2
9.1
9.6
8.7
10.1
9.7
8.5
10.8
10.3
10.9
10.6
10.6
11.7
10.1
9.7
12.3
10.8
8.8
10.3
10.4
10.4
10.9
11.2
10.4
9.4
11.6
10.6
10.9
10.7
8.4
After 9 Days
Treatment
Control
138.3
9.3
104
8.7
96.4
8.7
89
10.1
88
9.6
103.8
8.6
147.3
10.2
97.1
12.2
172.6
9.3
146.3
9.5
99
8.2
122.3
8.9
103
12.5
117.8
9.1
121.5
93
(a)
Use the given data for the treatment group to determine if there…
A deficiency of the trace element selenium in the diet can negatively impact growth, immunity, muscle and neuromuscular function, and fertility. The introduction of selenium supplements to dairy cows is justified when pastures have low selenium levels. Authors of a research paper supplied the following data on milk selenium concentration (mg/L) for a sample of cows given a selenium supplement (the treatment group) and a control sample given no supplement, both initially and after a 9-day period.
Initial Measurement
Treatment
Control
11.3
9.1
9.7
8.7
10.1
9.7
8.5
10.8
10.4
10.9
10.7
10.6
11.8
10.1
9.8
12.3
10.6
8.8
10.4
10.4
10.2
10.9
11.3
10.4
9.2
11.6
10.7
10.9
10.8
8.2
After 9 Days
Treatment
Control
138.3
9.4
104
8.8
96.4
8.8
89
10.1
88
9.7
103.8
8.7
147.3
10.3
97.1
12.3
172.6
9.4
146.3
9.5
99
8.3
122.3
8.9
103
12.5
117.8
9.1
121.5
93
(a)
Use the given data for the treatment group to determine if…
Chapter 12 Solutions
Mathematical Statistics with Applications
Ch. 12.2 - Suppose that you wish to compare the means for two...Ch. 12.2 - Refer to Exercise 12.1. Suppose that you allocate...Ch. 12.2 - Suppose, as in Exercise 12.1, that two populations...Ch. 12.2 - Refer to Exercise 12.3. How many observations are...Ch. 12.2 - Suppose that we wish to study the effect of the...Ch. 12.2 - Refer to Exercise 12.5. Consider two methods for...Ch. 12.2 - Refer to Exercise 12.5. Why might it be advisable...Ch. 12.2 - The standard error of the estimator 1 in a simple...Ch. 12.3 - Consider the data analyzed in Examples 12.2 and...Ch. 12.3 - Two computers often are compared by running a...
Ch. 12.3 - When Y1i, for i = 1, 2,, n, and Y2i, for i = 1,...Ch. 12.3 - Prob. 12ECh. 12.3 - Prob. 13ECh. 12.3 - Prob. 14ECh. 12.3 - A plant manager, in deciding whether to purchase a...Ch. 12.3 - Muck is the rich, highly organic type of soil that...Ch. 12.3 - Prob. 17ECh. 12.4 - Prob. 18ECh. 12.4 - Prob. 19ECh. 12.4 - Prob. 20ECh. 12.4 - Prob. 21ECh. 12.4 - Prob. 22ECh. 12.4 - Prob. 23ECh. 12.4 - Prob. 24ECh. 12.4 - Prob. 25ECh. 12.4 - Prob. 26ECh. 12.4 - Complete the assignment of treatments for the...Ch. 12 - Prob. 28SECh. 12 - Prob. 29SECh. 12 - Prob. 30SECh. 12 - Prob. 31SECh. 12 - Prob. 32SECh. 12 - Prob. 33SECh. 12 - Prob. 34SECh. 12 - The earths temperature affects seed germination,...Ch. 12 - An experiment was conducted to compare mean...Ch. 12 - Prob. 37SE
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