Introduction To Statistics And Data Analysis
6th Edition
ISBN: 9781337793612
Author: PECK, Roxy.
Publisher: Cengage Learning,
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Textbook Question
Chapter 11, Problem 86CR
The article “Truth and DARE: Tracking Drug Education to Graduation” (Social Problems [1994]: 448-456) compared the drug use of 288 randomly selected high school seniors exposed to a drug education program (DARE) and 335 randomly selected high school seniors who were not exposed to such a program. Data for marijuana use are given in the accompanying table. Is there evidence that the proportion using marijuana is lower for students exposed to the DARE program? Use α = 0.05.
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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
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.
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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 11 Solutions
Introduction To Statistics And Data Analysis
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Ch. 11.1 - Prob. 11ECh. 11.1 - The paper Mood Food: Chocolate and Depressive...Ch. 11.1 - The authors of the paper Influence of Biofeedback...Ch. 11.1 - Example 11.1 looked at a study comparing students...Ch. 11.1 - Internet addiction has been described as excessive...Ch. 11.1 - The paper Does the Color of the Mug Influence the...Ch. 11.1 - A newspaper story headline reads Gender Plays Part...Ch. 11.1 - The authors of the paper The Empowering (Super)...Ch. 11.1 - Fumonisins are environmental toxins produced by a...Ch. 11.1 - A researcher at the Medical College of Virginia...Ch. 11.1 - Do certain behaviors result in a severe drain on...Ch. 11.2 - Suppose that you were interested in investigating...Ch. 11.2 - Many runners believe that listening to music while...Ch. 11.2 - The study described in the previous exercise also...Ch. 11.2 - In Exercise 11.23, a hypothesis test leads to the...Ch. 11.2 - The article Puppy Love? Its Real, Study Says (USA...Ch. 11.2 - The authors of the paper Concordance of...Ch. 11.2 - The paper referenced in the previous exercise also...Ch. 11.2 - The paper Driving Performance While Using a Mobile...Ch. 11.2 - The paper referenced in the previous exercise also...Ch. 11.2 - Use the information given in the previous exercise...Ch. 11.2 - To determine if chocolate milk was as effective as...Ch. 11.2 - The humorous paper Will Humans Swim Faster or...Ch. 11.2 - The study described in the paper Marketing Actions...Ch. 11.2 - Head movement evaluations are important because...Ch. 11.2 - The paper Less Air Pollution Leads to Rapid...Ch. 11.2 - The paper The Truth About Lying in Online Dating...Ch. 11.2 - The paper Quantitative Assessment of Glenohumeral...Ch. 11.2 - Two proposed computer mouse designs were compared...Ch. 11.2 - The authors of the paper Ultrasound Techniques...Ch. 11.3 - Some people seem to believe that you can fix...Ch. 11.3 - The report titled Digital Democracy Survey (2016,...Ch. 11.3 - After the 2010 earthquake in Haiti, many...Ch. 11.3 - The article Most Women Oppose Having to Register...Ch. 11.3 - The article referenced in the previous exercise...Ch. 11.3 - The report Audience Insights: Communicating to...Ch. 11.3 - According to the U.S. Census Bureau, the...Ch. 11.3 - The article Fish Oil Staves Off Schizophrenia (USA...Ch. 11.3 - The report Young People Living on the Edge...Ch. 11.3 - The report Raising Kids and Running a Household:...Ch. 11.3 - The Bureau of Labor Statistics...Ch. 11.3 - The Bureau of Labor Statistics report referenced...Ch. 11.3 - The report The New Food Fights: U.S. Public...Ch. 11.3 - A survey of high school students is described in...Ch. 11.3 - The article Spray Flu Vaccine May Work Better Than...Ch. 11.3 - The following quote is from the article Canadians...Ch. 11.3 - A Harris Poll press release dated November 1,...Ch. 11.3 - Women diagnosed with breast cancer whose tumors...Ch. 11.3 - Gallup surveyed adult Americans about their...Ch. 11.4 - The paper The Psychological Consequences of Money...Ch. 11.4 - An experiment to determine if an online...Ch. 11.4 - The paper Ready or Not? Criteria for Marriage...Ch. 11.5 - Use the information given in the previous exercise...Ch. 11.5 - Prob. 66ECh. 11.5 - Prob. 68ECh. 11.5 - Prob. 70ECh. 11.6 - The article Rapid Evolutionary Response to a...Ch. 11.6 - Prob. 72ECh. 11.6 - Prob. 74ECh. 11.6 - Prob. 75ECh. 11.6 - As part of a study described in the report I Cant...Ch. 11.6 - Prob. 78ECh. 11 - A deficiency of the trace element selenium in the...Ch. 11 - Prob. 80CRCh. 11 - In a study of a proposed treatment for diabetes...Ch. 11 - When a surgeon repairs injuries, sutures (stitched...Ch. 11 - Prob. 83CRCh. 11 - In a study of memory recall, eight students from a...Ch. 11 - As part of a study to determine the effects of...Ch. 11 - The article Truth and DARE: Tracking Drug...Ch. 11 - The article Softball Sliding Injuries (American...Ch. 11 - Wayne Gretzky was one of ice hockeys most prolific...Ch. 11 - Heres one to sink your teeth into: The authors of...Ch. 11 - Dentists make many people nervous. To see whether...Ch. 11 - Both surface soil and subsoil specimens were taken...
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