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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Chapter 4.3, Problem 34PB
Vitamin B A New York Times article (March 13, 2006) described two studies in which subjects who had recently had a heart attack were randomly assigned to one of four treatments: placebo and three different doses of vitamin B. In each study, after years of study, the differences among the proportions having a heart attack were judged to be not statistically significant. Identify the (a) response variable, (b) explanatory variable, (c) experimental units, and (d) treatments and (e) explain what it means to say that differences “were judged to be not statistically significant.”
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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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