Statistics: The Art and Science of Learning from Data (4th Edition)
4th Edition
ISBN: 9780321997838
Author: Alan Agresti, Christine A. Franklin, Bernhard Klingenberg
Publisher: PEARSON
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Textbook Question
Chapter 1.2, Problem 19PB
Smoking cessation A study published in 2010 in The New England Journal of Medicine investigated the effect of financial incentives on smoking cessation. As part of the study, 878 employees of a company, all of whom were smokers, were randomly assigned to one of two treatment groups. One group (442 employees) was to receive information about smoking cessation programs; the other (436 employees) was to receive that same information as well as a financial incentive to quit smoking. The outcome of interest of the study was smoking cessation status six months after the initial cessation was reported. After implementation of the program, 14.7% of individuals in the financial incentive group reported cessation six months after the initial report, compared to 5.0% of the information-only group. Assume that the observed difference in cessation rates between the groups 114.7% – 5.0% = 9.7%2 is statistically significant.
- a. What does it mean to be statistically significant? (choose the best option from (i)–(iv))
- i. The financial option was offered to 9.7% more smokers in the study than the nonsmokers who were employees of the company.
- ii. 9.7% was calculated using statistical techniques.
- iii. If there were no true impact of the financial incentive, the observed difference of 9.7% is unlikely to have occurred by chance alone.
- iv. We know that if the financial incentive were given to all smokers, 9.7% would quit smoking.
- b. Is the difference between the groups attributable to the financial incentive?
- c. Is the difference between the groups attributable to the financial incentive?
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Chapter 1 Solutions
Statistics: The Art and Science of Learning from Data (4th Edition)
Ch. 1.1 - Aspirin and heart attacks The Harvard Medical...Ch. 1.1 - Poverty and race The Current Population Survey...Ch. 1.1 - GSS and heaven Go to the General Social Survey...Ch. 1.1 - GSS and heaven and hell Refer to the previous...Ch. 1.1 - GSS for subject you pick At the GSS website, click...Ch. 1.2 - Description and inference a. Distinguish between...Ch. 1.2 - Censorship The General Social Survey in 2012 asked...Ch. 1.2 - Concerned about global warming? The Institute for...Ch. 1.2 - Graduate school information Suppose a liberal arts...Ch. 1.2 - Prob. 10PB
Ch. 1.2 - Prob. 11PBCh. 1.2 - At what age did women marry? A historian wants to...Ch. 1.2 - Prob. 13PBCh. 1.2 - National service Consider the population of all...Ch. 1.2 - Samples vary less with more data Well see that the...Ch. 1.2 - Comparing polls The following table shows the...Ch. 1.2 - Prob. 18PBCh. 1.2 - Smoking cessation A study published in 2010 in The...Ch. 1.3 - Prob. 20PBCh. 1.3 - Shopping sales data file Construct a data file...Ch. 1.3 - Sample with caution Individuals with children who...Ch. 1.3 - Prob. 23PBCh. 1.3 - Use a data file with software You may need to...Ch. 1.3 - Prob. 25PBCh. 1.3 - Ebola outbreaks Ebola virus disease outbreaks have...Ch. 1 - UW Student survey In a University of Wisconsin...Ch. 1 - Euthanasia The General Social Survey asked, in...Ch. 1 - Prob. 30CPCh. 1 - Breaking down Brown versus Whitman Example 2 of...Ch. 1 - Online learning Your university is interested in...Ch. 1 - Prob. 33CPCh. 1 - Prob. 34CPCh. 1 - Prob. 35CPCh. 1 - True or false? In a particular study, you could...Ch. 1 - Prob. 39CPCh. 1 - Prob. 40CP
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