Statistics, Books a la Carte Edition Plus MyLab Statistics with Pearson eText -- Access Card Package (4th Edition)
4th Edition
ISBN: 9780134435855
Author: Alan Agresti, Christine A. Franklin, Bernhard Klingenberg
Publisher: PEARSON
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Chapter 4, Problem 68CP
Aspirin prevents heart attacks? During the 1980s approximately 22,000 physicians over the age of 40 agreed to participate in a long-term study called the Physicians’ Health Study. One question investigated was whether aspirin helps lower the rate of heart attacks. The physicians were randomly assigned to take aspirin or take a placebo.
- a. Identify the response variable and the explanatory variable.
- b. Explain why this is an experiment and identify the treatments.
- c. There are other explanatory variables, such as the amount of exercise a physician got, that we would expect to be associated with the response variable. Explain how such a variable is dealt with by the randomized nature of the experiment.
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Chapter 4 Solutions
Statistics, Books a la Carte Edition Plus MyLab Statistics with Pearson eText -- Access Card Package (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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