Introduction to Probability and Statistics
14th Edition
ISBN: 9781133103752
Author: Mendenhall, William
Publisher: Cengage Learning
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Textbook Question
Chapter 2, Problem 2.64SE
Sleep and the College Student How muchsleep do you get on a typical school night? A group of10 college students were asked to report the number ofhours that they slept on the previous night with the following results:
- Find the mean and the standard deviation of thenumber of hours of sleep for these 10 students.
- Calculate the z-score for the largest value
- What is the most frequently reported measurement?What is the name for this measure of center?
- Construct a box plot for the data. Does the boxplot confirm your results in part b? [HINT: Since thez-score and the box plot are two unrelated methodsfor detecting outliers, and use different types ofstatistics, they do not necessarily have to (butusually do) produce the same results.]
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Students have asked these similar questions
Question 1
The data shown in Table 1 are and R values for 24 samples of size n = 5 taken from a process producing
bearings. The measurements are made on the inside diameter of the bearing, with only the last three decimals
recorded (i.e., 34.5 should be 0.50345).
Table 1: Bearing Diameter Data
Sample Number
I
R
Sample Number
I R
1
34.5
3
13
35.4
8
2
34.2
4
14
34.0
6
3
31.6
4
15
37.1
5
4
31.5
4
16
34.9
7
5
35.0
5
17
33.5
4
6
34.1
6
18
31.7
3
7
32.6
4
19
34.0
8
8
33.8
3
20
35.1
9
34.8
7
21
33.7
2
10
33.6
8
22
32.8
1
11
31.9
3
23
33.5
3
12
38.6 9
24
34.2
2
(a) Set up and R charts on this process. Does the process seem to be in statistical control? If necessary,
revise the trial control limits. [15 pts]
(b) If specifications on this diameter are 0.5030±0.0010, find the percentage of nonconforming bearings pro-
duced by this process. Assume that diameter is normally distributed. [10 pts]
1
4. (5 pts) Conduct a chi-square contingency test (test of independence) to assess whether
there is an association between the behavior of the elderly person (did not stop to talk,
did stop to talk) and their likelihood of falling. Below, please state your null and
alternative hypotheses, calculate your expected values and write them in the table,
compute the test statistic, test the null by comparing your test statistic to the critical
value in Table A (p. 713-714) of your textbook and/or estimating the P-value, and
provide your conclusions in written form. Make sure to show your work.
Did not stop walking to talk
Stopped walking to talk
Suffered a fall
12
11
Totals
23
Did not suffer a fall | 2
Totals
35
37
14
46
60
T
Question 2
Parts manufactured by an injection molding process are subjected to a compressive strength test. Twenty samples
of five parts each are collected, and the compressive strengths (in psi) are shown in Table 2.
Table 2: Strength Data for Question 2
Sample Number
x1
x2
23
x4
x5
R
1
83.0
2
88.6 78.3 78.8
3
85.7
75.8
84.3
81.2 78.7 75.7 77.0
71.0 84.2
81.0
79.1
7.3
80.2 17.6
75.2
80.4
10.4
4
80.8
74.4
82.5
74.1 75.7 77.5
8.4
5
83.4
78.4
82.6 78.2
78.9
80.3
5.2
File Preview
6
75.3
79.9
87.3 89.7
81.8
82.8
14.5
7
74.5
78.0 80.8
73.4
79.7
77.3
7.4
8
79.2
84.4 81.5 86.0
74.5
81.1
11.4
9
80.5
86.2
76.2 64.1
80.2
81.4
9.9
10
75.7
75.2
71.1 82.1
74.3
75.7
10.9
11
80.0 81.5
78.4 73.8
78.1
78.4
7.7
12
80.6
81.8
79.3
73.8
81.7 79.4
8.0
13
82.7
81.3
79.1
82.0 79.5 80.9
3.6
14
79.2
74.9
78.6 77.7
75.3
77.1
4.3
15
85.5 82.1
82.8 73.4
71.7
79.1
13.8
16
78.8 79.6
80.2 79.1
80.8 79.7
2.0
17
82.1
78.2
18
84.5
76.9
75.5
83.5 81.2
19
79.0 77.8
20
84.5
73.1
78.2 82.1
79.2 81.1 7.6
81.2 84.4 81.6 80.8…
Chapter 2 Solutions
Introduction to Probability and Statistics
Ch. 2.2 - You are given n=5 measurements: 0, 5, 1, 1,3. Draw...Ch. 2.2 - Prob. 2.2ECh. 2.2 - Prob. 2.3ECh. 2.2 - Auto Insurance The cost of automobile insurance...Ch. 2.2 - Prob. 2.5ECh. 2.2 - Prob. 2.6ECh. 2.2 - Prob. 2.7ECh. 2.2 - Prob. 2.8ECh. 2.2 - Prob. 2.9ECh. 2.2 - Prob. 2.10E
Ch. 2.2 - Prob. 2.11ECh. 2.2 - Prob. 2.12ECh. 2.3 - You are given n=5 measurements: 2, 1, 1,3,5. a....Ch. 2.3 - Prob. 2.14ECh. 2.3 - Prob. 2.15ECh. 2.3 - Prob. 2.16ECh. 2.3 - Prob. 2.17ECh. 2.3 - Utility Bills in Southern CaliforniaThe monthly...Ch. 2.5 - Prob. 2.19ECh. 2.5 - Prob. 2.20ECh. 2.5 - A distribution of measurements is relatively...Ch. 2.5 - Prob. 2.22ECh. 2.5 - Prob. 2.23ECh. 2.5 - Packaging Hamburger Meat The data listed here are...Ch. 2.5 - Breathing Rates Is your breathing rate normal?...Ch. 2.5 - Prob. 2.26ECh. 2.5 - Social Security Numbers A group of70 students were...Ch. 2.5 - Prob. 2.28ECh. 2.5 - Prob. 2.29ECh. 2.5 - Prob. 2.30ECh. 2.5 - Timber Tracts To estimate the amount of lumber in...Ch. 2.5 - Prob. 2.32ECh. 2.5 - Prob. 2.33ECh. 2.5 - Prob. 2.34ECh. 2.5 - Prob. 2.35ECh. 2.5 - Prob. 2.36ECh. 2.5 - Prob. 2.37ECh. 2.5 - Prob. 2.38ECh. 2.5 - Prob. 2.39ECh. 2.7 - Prob. 2.40ECh. 2.7 - Find the five-number summary and the IQR forthese...Ch. 2.7 - Given the following data set: 2.3, 1.0, 2.1, 6.5,...Ch. 2.7 - Given the following data set: .23, .30, .35, .41,...Ch. 2.7 - Construct a box plot for these data and...Ch. 2.7 - Construct a box plot for these data and...Ch. 2.7 - If you scored at the 69th percentile on a...Ch. 2.7 - Mercury Concentration in DolphinsEnvironmental...Ch. 2.7 - Hamburger Meat The weights (in pounds) of the 27...Ch. 2.7 - Comparing NFL Quarterbacks How does Aaron Rodgers,...Ch. 2.7 - Presidential Vetoes The set of presidential vetoes...Ch. 2.7 - Survival Times Altman and Bland report the...Ch. 2.7 - Utility Bills in Southern California, again The...Ch. 2.7 - What’s Normal? again Refer to Exercise1.67 and...Ch. 2 - Raisins The number of raisins in each of...Ch. 2 - Prob. 2.55SECh. 2 - Prob. 2.56SECh. 2 - A Recurring IIIness Refer to Exercise 1.26 and...Ch. 2 - Prob. 2.58SECh. 2 - Prob. 2.59SECh. 2 - Tuna Fish, again Refer to Exercise 2.8. Theprices...Ch. 2 - Prob. 2.61SECh. 2 - Chloroform According to the EPA, Chloroform, which...Ch. 2 - Prob. 2.63SECh. 2 - Sleep and the College Student How muchsleep do you...Ch. 2 - Prob. 2.65SECh. 2 - Prob. 2.66SECh. 2 - Polluted Seawater Petroleum pollution in seasand...Ch. 2 - Prob. 2.68SECh. 2 - Prob. 2.69SECh. 2 - Prob. 2.70SECh. 2 - Prob. 2.71SECh. 2 - Prob. 2.72SECh. 2 - Prob. 2.73SECh. 2 - Prob. 2.74SECh. 2 - TV Commercials The mean duration oftelevision...Ch. 2 - Prob. 2.76SECh. 2 - Prob. 2.77SECh. 2 - Prob. 2.78SECh. 2 - Prob. 2.79SECh. 2 - Prob. 2.80SECh. 2 - Prob. 2.81SECh. 2 - Prob. 2.82SECh. 2 - Prob. 2.83SECh. 2 - Prob. 2.84SECh. 2 - Prob. 2.85SE
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- Name: Lab Time: Quiz 7 & 8 (Take Home) - due Wednesday, Feb. 26 Contingency Analysis (Ch. 9) In lab 5, part 3, you will create a mosaic plot and conducted a chi-square contingency test to evaluate whether elderly patients who did not stop walking to talk (vs. those who did stop) were more likely to suffer a fall in the next six months. I have tabulated the data below. Answer the questions below. Please show your calculations on this or a separate sheet. Did not stop walking to talk Stopped walking to talk Totals Suffered a fall Did not suffer a fall Totals 12 11 23 2 35 37 14 14 46 60 Quiz 7: 1. (2 pts) Compute the odds of falling for each group. Compute the odds ratio for those who did not stop walking vs. those who did stop walking. Interpret your result verbally.arrow_forwardSolve please and thank you!arrow_forward7. In a 2011 article, M. Radelet and G. Pierce reported a logistic prediction equation for the death penalty verdicts in North Carolina. Let Y denote whether a subject convicted of murder received the death penalty (1=yes), for the defendant's race h (h1, black; h = 2, white), victim's race i (i = 1, black; i = 2, white), and number of additional factors j (j = 0, 1, 2). For the model logit[P(Y = 1)] = a + ß₁₂ + By + B²², they reported = -5.26, D â BD = 0, BD = 0.17, BY = 0, BY = 0.91, B = 0, B = 2.02, B = 3.98. (a) Estimate the probability of receiving the death penalty for the group most likely to receive it. [4 pts] (b) If, instead, parameters used constraints 3D = BY = 35 = 0, report the esti- mates. [3 pts] h (c) If, instead, parameters used constraints Σ₁ = Σ₁ BY = Σ; B = 0, report the estimates. [3 pts] Hint the probabilities, odds and odds ratios do not change with constraints.arrow_forward
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