Statistical Techniques in Business and Economics
18th Edition
ISBN: 9781260579611
Author: Douglas Lind; William Marchal; Samuel Wathen
Publisher: MCGRAW-HILL HIGHER EDUCATION
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Question
Chapter 1, Problem 21DA
a.
To determine
To verify: The variables are qualitative or quantitative.
b.
To determine
To identify: The level of measurement of each variable.
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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
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Months
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2
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Let x be a random variable indicating the number of months a person is unemployed.
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1
2
3
4
5
6
7
8
9
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b. Show that your probability distribution satisfies the conditions for a valid discrete probability distribution.
The input in the box below will not be graded, but may be reviewed and considered by your instructor.
blank
c. What is the probability that a…
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.
Working with a consultant, the management of MCC has developed the following probability distribution for x = the number of new clients for marriage counseling for the next year.
Excel File: data05-19.xls
x
10
f(x)
.05
20
30
.10
.10
40
.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
Variance
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.
Months
Unemployed
Number
Unemployed
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).
(x)
f(x)
1
2
3
4
5
6
7
8
9
10
b. Show that your probability distribution satisfies the conditions for a valid discrete probability distribution.
The input in the box below will not be graded, but may be reviewed and considered by your instructor.
c. What is the probability that a person…
Chapter 1 Solutions
Statistical Techniques in Business and Economics
Ch. 1 - Prob. 1SRCh. 1 - (a) The mean age of people who listen to talk...Ch. 1 - What is the level of measurement for each of the...Ch. 1 - Slate is a daily magazine on the Web. Its business...Ch. 1 - Prob. 3ECh. 1 - For each of the following, determine whether the...Ch. 1 - Explain the difference between qualitative and...Ch. 1 - Explain the difference between a sample and a...Ch. 1 - Prob. 7CECh. 1 - Prob. 8CE
Ch. 1 - Exits along Interstate highways were formerly...Ch. 1 - A poll solicits a large number of college...Ch. 1 - Best Buy sells Fitbit wearable technology products...Ch. 1 - Using the concepts of sample and population,...Ch. 1 - Place these variables in the following...Ch. 1 - Prob. 14CECh. 1 - Prob. 15CECh. 1 - AVX Home Entertainment, Inc., recently began a...Ch. 1 - Prob. 17CECh. 1 - The following chart depicts the average amounts...Ch. 1 - Prob. 19CECh. 1 - Refer to the North Valley Real Estate data, which...Ch. 1 - Prob. 21DACh. 1 - Refer to the Lincolnville School District bus...
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