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 9, Problem 104CP
To determine
Delineate the factors that cause different medical studies to draw different conclusions.
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A U.S. study published in The American Journal of Preventive Medicine compared state-level prevalence of firearm ownership in 2002 with state-level rates of firearm assault and firearm robbery in the subsequent year. The investigators found a positive association - meaning that states with higher prevalence of firearm ownership also tended to be the states with higher rates of firearm assault.
Which design best describes this study?
a)Observational cohort study
b)Randomized trial
c)Case-control study
d)Ecological study
W. Thomas Boyce, a professor and pediatrician at the University of British Columbia, Vancouver, has studied interactions between individual differences in physiology and differences in experience in determining health and well-being. Dr. Boyce found that some children are more sensitive to their environments. They do exceptionally well when the environment is supportive but are much more likely to have mental and physical health problems when the environment has challenges.
You decide to do a similar study, conducting a factorial experiment to test the effectiveness of one environmental factor and one physiological factor on a physical health outcome. As the environmental factor, you choose two levels of stressful life events. As the physiological factor, you choose three levels of immune reactivity. The outcome is number of respiratory illnesses in the previous 12 months, and the research participants are kindergartners.
In a study of reading comprehension, sixth grade students read a short story about baseball. The students are divided into two groups based on their knowledge of baseball. Within each group, half of the students are high scorers on a test of verbal IQ, while the remaining students are low scorers. She found:
Low baseball
High baseball
Low IQ-V
20
25
High IQ-V
20
30
What is the main effect of baseball knowledge?
those in the high knowledge group score lower on reading comprehension than those in the low knowledge group.
there is no main effect of baseball knowledge
those in the high verbal IQ group score higher on reading comprehension than those in the low verbal IQ group.
those in the high knowledge group score higher on reading comprehension than those in the low knowledge group.
Chapter 9 Solutions
Statistics: The Art and Science of Learning from Data (4th Edition)
Ch. 9.1 - H0 or Ha? For parts a and b, is the statement a...Ch. 9.1 - H0 or Ha? For each of the following, is the...Ch. 9.1 - Burden of proof For a new pesticide, should the...Ch. 9.1 - Financial aid The average financial aid package...Ch. 9.1 - Low-carbohydrate diet A study plans to have a...Ch. 9.1 - Prob. 6PBCh. 9.1 - Proper hypotheses? Explain what is wrong with each...Ch. 9.1 - Prob. 8PBCh. 9.1 - P-value Indicate whether each of the following...Ch. 9.2 - Psychic A person who claims to be psychic says he...
Ch. 9.2 - Prob. 11PBCh. 9.2 - Get P-value from z For a test of H0: p = 0.50, the...Ch. 9.2 - Get more P-values from z Refer to the previous...Ch. 9.2 - Find test statistic and P-value For a test of H0:...Ch. 9.2 - Dogs and cancer A recent study4 considered whether...Ch. 9.2 - Religion important in your life? Americans ages 18...Ch. 9.2 - Prob. 17PBCh. 9.2 - Prob. 18PBCh. 9.2 - Testing a headache remedy Studies that compare...Ch. 9.2 - Gender bias in selecting managers For a large...Ch. 9.2 - Gender discrimination Refer to the 95% confidence...Ch. 9.2 - Garlic to repel ticks A study (J. Amer. Med....Ch. 9.2 - Exit-poll predictions According to an exit poll of...Ch. 9.2 - Which cola? The 49 students in a class at the...Ch. 9.2 - How to sell a burger A fast-food chain wants to...Ch. 9.2 - A binomial headache A null hypothesis states that...Ch. 9.2 - P-value for small samples Example 4, on whether...Ch. 9.3 - Which t has P-value = 0.05? A t test for a mean...Ch. 9.3 - Practice mechanics of a t test A study has a...Ch. 9.3 - Prob. 30PBCh. 9.3 - Low carbohydrate diet In a recent study,8 272...Ch. 9.3 - Prob. 32PBCh. 9.3 - Facebook friends Many students brag that they have...Ch. 9.3 - Lake pollution An industrial plant claims to...Ch. 9.3 - Weight change for controls A disadvantage of the...Ch. 9.3 - Crossover study A crossover study of 13 children...Ch. 9.3 - Too little or too much wine? Wine-pouring vending...Ch. 9.3 - Prob. 38PBCh. 9.3 - Assumptions important? Refer to the previous...Ch. 9.3 - Anorexia in teenage girls Example 8 described a...Ch. 9.3 - Sensitivity study Ideally, results of a...Ch. 9.3 - Prob. 42PBCh. 9.4 - Dr. Dog In the experiment in Example 4, we got a...Ch. 9.4 - Error probability A significance test about a...Ch. 9.4 - Fracking errors Example 6, in testing H0: p = 0.5...Ch. 9.4 - Prob. 46PBCh. 9.4 - Anorexia decision Refer to the previous exercise....Ch. 9.4 - Prob. 48PBCh. 9.4 - Errors in medicine Consider the test of H0: The...Ch. 9.4 - Prob. 50PBCh. 9.4 - Detecting prostate cancer Refer to the previous...Ch. 9.4 - Prob. 52PBCh. 9.5 - Misleading summaries? Two researchers conduct...Ch. 9.5 - Practical significance A study considers whether...Ch. 9.5 - Prob. 55PBCh. 9.5 - Fishing for significance A marketing study...Ch. 9.5 - Prob. 57PBCh. 9.5 - Prob. 58PBCh. 9.5 - Interpret medical research studies a. An...Ch. 9.6 - Find P(Type II error) A study is designed to test...Ch. 9.6 - Gender bias in selecting managers Exercise 9.20...Ch. 9.6 - Prob. 62PBCh. 9.6 - P(Type II error) large when p close to H0 For...Ch. 9.6 - Prob. 64PBCh. 9.6 - Power for infertility trial Consider Example 13...Ch. 9.6 - Exploring Type II errors Refer to the web app from...Ch. 9 - H0 or Ha? For each of the following hypotheses,...Ch. 9 - Write H0 and Ha For each of the following...Ch. 9 - Prob. 69CPCh. 9 - Free-throw accuracy Consider all cases in which a...Ch. 9 - Brown or Whitman? Californias governor election in...Ch. 9 - Prob. 72CPCh. 9 - Prob. 73CPCh. 9 - Prob. 74CPCh. 9 - Prob. 75CPCh. 9 - Start a hockey team A fraternity at a university...Ch. 9 - Prob. 77CPCh. 9 - Prob. 78CPCh. 9 - Prob. 79CPCh. 9 - Prob. 80CPCh. 9 - Prob. 81CPCh. 9 - Two ideal children? Is the ideal number of...Ch. 9 - Prob. 83CPCh. 9 - Prob. 84CPCh. 9 - Blood pressure When Vincenzo Baranellos blood...Ch. 9 - Increasing blood pressure In the previous...Ch. 9 - Tennis balls in control? When it is operating...Ch. 9 - Prob. 88CPCh. 9 - Prob. 89CPCh. 9 - CI and test Refer to the previous exercise. a. For...Ch. 9 - Prob. 91CPCh. 9 - Religious beliefs statistically significant? A...Ch. 9 - Prob. 93CPCh. 9 - Prob. 94CPCh. 9 - Prob. 95CPCh. 9 - Prob. 96CPCh. 9 - Prob. 98CPCh. 9 - Baseball home team advantage In Major League...Ch. 9 - Prob. 100CPCh. 9 - Prob. 101CPCh. 9 - Prob. 102CPCh. 9 - Prob. 103CPCh. 9 - Prob. 104CPCh. 9 - Prob. 105CPCh. 9 - Prob. 106CPCh. 9 - Prob. 107CPCh. 9 - Prob. 108CPCh. 9 - Significance Explain the difference between...Ch. 9 - More doctors recommend An advertisement by Company...Ch. 9 - Prob. 111CPCh. 9 - Bad P-value interpretations A random sample of...Ch. 9 - Prob. 113CPCh. 9 - Prob. 114CPCh. 9 - Prob. 115CPCh. 9 - Prob. 116CPCh. 9 - Prob. 117CPCh. 9 - Prob. 118CPCh. 9 - Prob. 119CPCh. 9 - Prob. 120CPCh. 9 - Prob. 121CPCh. 9 - True or false A 95% confidence interval for =...Ch. 9 - Prob. 123CPCh. 9 - Prob. 124CPCh. 9 - Prob. 125CPCh. 9 - Prob. 126CPCh. 9 - Prob. 127CPCh. 9 - Prob. 128CP
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