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 4.3, Problem 35PB
Facebook study During the one-week period of January 11–18, 2012, Facebook conducted an experiment to research whether emotional states can be transferred to others via emotional contagion. Facebook users were randomly selected to be part of two parallel studies in which Facebook manipulated the exposure to emotional expressions in the user’s news feed. Two parallel experiments were conducted. In one study, it reduced the positive emotional content; in the other study, the negative emotional content was reduced. For each study, there was a control group (the users’ news feed was not manipulated), and an experimental group (the users’ news feed was manipulated—either positively or negatively). Two variables were measured in each study after the manipulation by Facebook: the percentage of all words produced by a person that was positive and the percentage of all words produced by a person that was negative. There were 689,003 Facebook users in the study. (Source: PNAS, June 17, 2014, vol. 111, no. 24, www.pnas.org/cgi/doi/10.1073/pnas.1320040111)
- a. Explain why this study is an experiment.
- b. Identity the experimental units.
- c. For the study in which exposure to friends’ positive emotional content was reduced, identity the explanatory variable and the two response variables.
- d. The Facebook users randomly selected for the study were unaware they were part of this experiment. Provide a reason Facebook elected not to inform the selected users that they were part of an experiment. Provide a reason the users selected for the study may have felt not informing them about the study was unethical.
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Chapter 4 Solutions
Statistics: The Art and Science of Learning from Data (4th Edition)
Ch. 4.1 - Cell phones Consider the cell phone Study 3...Ch. 4.1 - High blood pressure and binge drinking Many...Ch. 4.1 - Low-fat versus low-carb diet? One hundred...Ch. 4.1 - Experiments versus observational studies When...Ch. 4.1 - School testing for drugs Example 3 discussed a...Ch. 4.1 - Hormone therapy and heart disease Since 1976 the...Ch. 4.1 - Speaking foreign languages A 2014 study...Ch. 4.1 - Breast-cancer screening A study published in 2010...Ch. 4.1 - Experiment or observe? Explain whether an...Ch. 4.1 - Baseball under a full moon During a baseball game...
Ch. 4.1 - Seat belt anecdote Andy once heard about a car...Ch. 4.1 - Poker as a profession? Tonys mother is extremely...Ch. 4.1 - Whats more to blame for obesity? In a study...Ch. 4.1 - Census every 10 years? A nationwide census is...Ch. 4.2 - Choosing officers A campus club consists of five...Ch. 4.2 - Simple random sample of students In Example 4, a...Ch. 4.2 - Auditing accountsapp Use an app or computer...Ch. 4.2 - Sampling from a directory A local telephone...Ch. 4.2 - Bias due to perceived race A political scientist...Ch. 4.2 - Confederates Some southern states in the United...Ch. 4.2 - Instructor ratings The website...Ch. 4.2 - Job trends The 20132014 Recruiting Trends report,...Ch. 4.2 - Gun control More than 75% of Americans answer yes...Ch. 4.2 - Violent video games and family closeness A recent...Ch. 4.2 - Fracking The journal Energy Policy (2014, 65:...Ch. 4.2 - Teens buying alcohol over Internet In August 2006,...Ch. 4.2 - Cheating spouses and bias In a survey conducted by...Ch. 4.2 - Online dating A story titled Personals, Sex Sites...Ch. 4.2 - Identify the bias A newspaper designs a survey to...Ch. 4.2 - Types of bias Give an example of a survey that...Ch. 4.3 - Smoking affects lung cancer? You would like to...Ch. 4.3 - Never leave home without duct tape There have been...Ch. 4.3 - More duct tape In a follow-up study, 103 patients...Ch. 4.3 - Vitamin B A New York Times article (March 13,...Ch. 4.3 - Facebook study During the one-week period of...Ch. 4.3 - Science faculty selection of grad students In an...Ch. 4.3 - Pain reduction medication Consider an experiment...Ch. 4.3 - Pain reduction medication, continued Consider the...Ch. 4.3 - Pain reduction medication, yet again Revisit the...Ch. 4.3 - Colds and vitamin C For some time there has been...Ch. 4.3 - Reducing high blood pressure A pharmaceutical...Ch. 4.4 - Student loan debt A researcher wants to compare...Ch. 4.4 - Club officers again In Exercise 4.15, two officers...Ch. 4.4 - Security awareness training Of 400 employees at a...Ch. 4.4 - Prob. 45PBCh. 4.4 - Prob. 46PBCh. 4.4 - Prob. 47PBCh. 4.4 - Prob. 48PBCh. 4.4 - Prob. 49PBCh. 4.4 - Prob. 50PBCh. 4.4 - Prob. 51PBCh. 4.4 - Prob. 52PBCh. 4.4 - Effect of partner smoking in smoking cessation...Ch. 4 - Cell phones If you want to conduct a study with...Ch. 4 - Observational versus experimental study Without...Ch. 4 - Unethical experimentation Give an example of a...Ch. 4 - Spinal fluid proteins and Alzheimers A research...Ch. 4 - Fear of asbestos Your friend reads about a study...Ch. 4 - NCAA mens basketball poll The last four teams of...Ch. 4 - Sampling your fellow students You are assigned to...Ch. 4 - Prob. 61CPCh. 4 - Comparing female and male students You plan to...Ch. 4 - Football discipline A large southern university...Ch. 4 - Prob. 64CPCh. 4 - Voluntary sports polls In 2014, the Pittsburgh...Ch. 4 - Video games mindless? Playing video games not so...Ch. 4 - Physicians health study Read about the first...Ch. 4 - Aspirin prevents heart attacks? During the 1980s...Ch. 4 - Prob. 69CPCh. 4 - Prob. 70CPCh. 4 - Prob. 71CPCh. 4 - Bupropion and nicotine patch study results The...Ch. 4 - Prefer Coke or Pepsi? You want to conduct an...Ch. 4 - Prob. 74CPCh. 4 - Samples not equally likely in a cluster sample? In...Ch. 4 - Nursing homes You plan to sample residents of...Ch. 4 - Multistage health survey A researcher wants to...Ch. 4 - Hazing Hazing within college fraternities is a...Ch. 4 - Prob. 79CPCh. 4 - Twins and breast cancer Excessive cumulative...Ch. 4 - Judging sampling design In each of the following...Ch. 4 - Prob. 87CPCh. 4 - Age for legal alcohol You want to investigate the...Ch. 4 - Prob. 89CPCh. 4 - Prob. 90CPCh. 4 - Issues in clinical trials A randomized clinical...Ch. 4 - Prob. 92CPCh. 4 - Prob. 93CPCh. 4 - Prob. 94CPCh. 4 - Prob. 95CPCh. 4 - Prob. 96CPCh. 4 - For Exercises 4.974.103, select the best response....Ch. 4 - Prob. 98CPCh. 4 - For Exercises 4.974.103, select the best response....Ch. 4 - For Exercises 4.974.103, select the best response....Ch. 4 - Prob. 101CPCh. 4 - For Exercises 4.974.103, select the best response....Ch. 4 - Prob. 103CPCh. 4 - Systematic sampling A researcher wants to select...Ch. 4 - Prob. 106CPCh. 4 - Prob. 107CP
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