Introductory Statistics (10th Edition)
10th Edition
ISBN: 9780321989178
Author: Neil A. Weiss
Publisher: PEARSON
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Chapter 15, Problem 16RP
For Problems 14–17, presume that the variables student-to-faculty ratio and graduation rate satisfy the assumptions for regression inferences.
16. Graduation Rates. Refer to Problems 11 and 12.
- a. Find the predicted graduation rate for a university that has a student-to-faculty ratio of 17.
- b. Find a 95% prediction interval for the graduation rate of a university that has a student-to-faculty ratio of 17.
- c. Explain why the prediction interval in part (b) is wider than the confidence interval in Problem 15(b).
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West Virginia has one of the highest divorce rates in the nation, with an annual rate of approximately 5 divorces per 1000 people (Centers for Disease Control and Prevention website, January 12, 2012). The Marital Counseling Center, Inc. (MCC) thinks that the high divorce rate in the state may require them to hire additional staff.
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Excel File: data05-19.xls
x
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f(x)
.05
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.10
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.20
50
60
.35
.20
a. Is this probability distribution valid?
- Select your answer-
Explain.
f(x)
Σf(x)
Select your answer
Select your answer
b. What is the probability MCC will obtain more than 30 new clients (to 2 decimals)?
c. What is the probability MCC will obtain fewer than 20 new clients (to 2 decimals)?
d. Compute the expected value and variance of x.
Expected value
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clients per year
squared clients per year
For unemployed persons in the United States, the average number of months of unemployment at the end of December 2009 was approximately seven months (Bureau of Labor Statistics, January 2010). Suppose the following data are for a particular region in upstate New York. The values in the first column show the number of
months unemployed and the values in the second column show the corresponding number of unemployed persons.
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1
1029
2
1686
3
2269
4
2675
5
3487
6
4652
7
4145
8
3587
9
2325
10
1120
Let x be a random variable indicating the number of months a person is unemployed.
a. Use the data to develop an empirical discrete probability distribution for x (to 4 decimals).
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3
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6
7
8
9
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b. Show that your probability distribution satisfies the conditions for a valid discrete probability distribution.
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c. What is the probability that a person…
Chapter 15 Solutions
Introductory Statistics (10th Edition)
Ch. 15.1 - Suppose that x and y are predictor and response...Ch. 15.1 - Prob. 2ECh. 15.1 - Prob. 3ECh. 15.1 - Prob. 4ECh. 15.1 - Prob. 5ECh. 15.1 - In Exercises 15.315.6, assume that the variables...Ch. 15.1 - The difference between an observed value and a...Ch. 15.1 - Identify two graphs used in a residual analysis to...Ch. 15.1 - Which graph used in a residual analysis provides...Ch. 15.1 - Figure 15.8 shows three residual plots and a...
Ch. 15.1 - Figure 15.9 on the next page shows three residual...Ch. 15.1 - In Exercises 15.1215.21, we repeat the data and...Ch. 15.1 - In Exercises 15.1215.21, we repeat the data and...Ch. 15.1 - Prob. 14ECh. 15.1 - Prob. 15ECh. 15.1 - Prob. 16ECh. 15.1 - Prob. 17ECh. 15.1 - Prob. 18ECh. 15.1 - Prob. 19ECh. 15.1 - Prob. 20ECh. 15.1 - Prob. 21ECh. 15.1 - Prob. 22ECh. 15.1 - Prob. 23ECh. 15.1 - Prob. 24ECh. 15.1 - Prob. 25ECh. 15.1 - In Exercises 15.2215.27, we repeat the information...Ch. 15.1 - Prob. 27ECh. 15.1 - Prob. 28ECh. 15.1 - In Exercises 15.2815.33, a. compute the standard...Ch. 15.1 - Prob. 30ECh. 15.1 - In Exercises 15.2815.33, a. compute the standard...Ch. 15.1 - In Exercises 15.2815.33, a. compute the standard...Ch. 15.1 - In Exercises 15.2815.33, a. compute the standard...Ch. 15.1 - In Exercises 15.3415.43, use the technology of...Ch. 15.1 - In Exercises 15.3415.43, use the technology of...Ch. 15.1 - In Exercises 15.3415.43, use the technology of...Ch. 15.1 - In Exercises 15.3415.43, use the technology of...Ch. 15.1 - Prob. 38ECh. 15.1 - Prob. 39ECh. 15.1 - Prob. 40ECh. 15.1 - Prob. 41ECh. 15.1 - Prob. 42ECh. 15.1 - Prob. 43ECh. 15.2 - Explain why the predictor variable is useless as a...Ch. 15.2 - Prob. 45ECh. 15.2 - Prob. 46ECh. 15.2 - In this section, we used the statistic b1 as a...Ch. 15.2 - In Exercises 15.4815.57, we repeat the information...Ch. 15.2 - Prob. 49ECh. 15.2 - In Exercises 15.4815.57, we repeat the information...Ch. 15.2 - In Exercises 15.4815.57, we repeat the information...Ch. 15.2 - Prob. 52ECh. 15.2 - Prob. 53ECh. 15.2 - Prob. 54ECh. 15.2 - In Exercises 15.4815.57, we repeat the information...Ch. 15.2 - Prob. 56ECh. 15.2 - Prob. 57ECh. 15.2 - Prob. 58ECh. 15.2 - In Exercises 15.5815.63, we repeat the information...Ch. 15.2 - Prob. 60ECh. 15.2 - In Exercises 15.5815.63, we repeat the information...Ch. 15.2 - Prob. 62ECh. 15.2 - In Exercises 15.5815.63, we repeat the information...Ch. 15.2 - Prob. 64ECh. 15.2 - In each of Exercises 15.6415.69, apply Procedure...Ch. 15.2 - In each of Exercises 15.6415.69, apply Procedure...Ch. 15.2 - Prob. 67ECh. 15.2 - Prob. 68ECh. 15.2 - Prob. 69ECh. 15.2 - Prob. 70ECh. 15.2 - In Exercises 15.7015.80, use the technology of...Ch. 15.2 - In Exercises 15.7015.80, use the technology of...Ch. 15.2 - Prob. 73ECh. 15.2 - Prob. 74ECh. 15.2 - Prob. 75ECh. 15.2 - In Exercises 15.7015.80, use the technology of...Ch. 15.2 - Prob. 77ECh. 15.2 - Prob. 78ECh. 15.2 - In Exercises 15.7015.80, use the technology of...Ch. 15.2 - Prob. 80ECh. 15.3 - Without doing any calculations, fill in the blank....Ch. 15.3 - Prob. 82ECh. 15.3 - Prob. 83ECh. 15.3 - Prob. 84ECh. 15.3 - In Exercises 15.8215.91, we repeat the data from...Ch. 15.3 - Prob. 86ECh. 15.3 - Prob. 87ECh. 15.3 - In Exercises 15.8215.91, we repeat the data from...Ch. 15.3 - Prob. 89ECh. 15.3 - Prob. 90ECh. 15.3 - Prob. 91ECh. 15.3 - Prob. 92ECh. 15.3 - In Exercises 15.9215.97, presume that the...Ch. 15.3 - In Exercises 15.9215.97, presume that the...Ch. 15.3 - In Exercises 15.9215.9, presume that the...Ch. 15.3 - Prob. 96ECh. 15.3 - In Exercises 15.9215.97, presume that the...Ch. 15.3 - Prob. 98ECh. 15.3 - In Exercises 15.9815.108, use the technology of...Ch. 15.3 - In Exercises 15.9815.108, use the technology of...Ch. 15.3 - In Exercises 15.9815.108, use the technology of...Ch. 15.3 - In Exercises 15.9815.108, use the technology of...Ch. 15.3 - Prob. 103ECh. 15.3 - Prob. 104ECh. 15.3 - Prob. 105ECh. 15.3 - Prob. 106ECh. 15.3 - In Exercises 15.9815.108, use the technology of...Ch. 15.3 - Prob. 108ECh. 15.3 - Margin of Error in Regression. In Exercises 15.109...Ch. 15.3 - Refer to the confidence interval and prediction...Ch. 15.4 - Identify the statistic used to estimate the...Ch. 15.4 - Prob. 112ECh. 15.4 - Suppose that, for a sample of pairs of...Ch. 15.4 - Prob. 114ECh. 15.4 - Prob. 115ECh. 15.4 - Prob. 116ECh. 15.4 - Prob. 117ECh. 15.4 - Prob. 118ECh. 15.4 - Prob. 119ECh. 15.4 - Prob. 120ECh. 15.4 - Prob. 121ECh. 15.4 - Prob. 122ECh. 15.4 - Prob. 123ECh. 15.4 - Prob. 124ECh. 15.4 - Prob. 125ECh. 15.4 - Prob. 126ECh. 15.4 - Prob. 127ECh. 15.4 - Prob. 128ECh. 15.4 - Prob. 129ECh. 15.4 - Prob. 130ECh. 15.4 - Prob. 131ECh. 15.4 - Prob. 132ECh. 15.4 - Prob. 133ECh. 15.4 - In each of Exercises 15.13415.144, use the...Ch. 15.4 - In each of Exercises 15.13415.144, use the...Ch. 15.4 - Prob. 136ECh. 15.4 - Prob. 137ECh. 15.4 - Prob. 138ECh. 15.4 - Prob. 139ECh. 15.4 - Prob. 140ECh. 15.4 - In each of Exercises 15.13415.144, use the...Ch. 15.4 - Prob. 142ECh. 15.4 - Prob. 143ECh. 15.4 - Prob. 144ECh. 15 - Prob. 1RPCh. 15 - Suppose that x and y are two variables of a...Ch. 15 - What two plots did we use in this chapter to...Ch. 15 - Regarding analysis of residuals, decide in each...Ch. 15 - Suppose that you perform a hypothesis test for the...Ch. 15 - Prob. 6RPCh. 15 - Prob. 7RPCh. 15 - Prob. 8RPCh. 15 - Prob. 9RPCh. 15 - Identify the relationship between two variables...Ch. 15 - Graduation Rates. Graduation ratethe percentage of...Ch. 15 - Prob. 12RPCh. 15 - Prob. 13RPCh. 15 - For Problems 1417, presume that the variables...Ch. 15 - For Problems 1417, presume that the variables...Ch. 15 - For Problems 1417, presume that the variables...Ch. 15 - Prob. 17RPCh. 15 - In Problems 1820, use the technology of your...Ch. 15 - In Problems 1820, use the technology of your...Ch. 15 - In Problems 1820, use the technology of your...Ch. 15 - Recall from Chapter 1 (see page 34) that the Focus...Ch. 15 - At the beginning of this chapter, we presented...
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