Elementary Statistics (13th Edition)
13th Edition
ISBN: 9780134462455
Author: Mario F. Triola
Publisher: PEARSON
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Chapter 1, Problem 3RE
Sample Design Literacy In “Cardiovascular Effects of Intravenous Triiodothyronine in Patients Undergoing Coronary Artery Bypass Graft Surgery” [Journal of the American Medical Association (JAMA), Vol 275, No. 9, the authors explain that patients were assigned to one of three groups: (1) a group treated with triidothyronine. (2) a group treated with normal saline bolus and dopamine, and (3) a placebo group given normal saline. The authors summarize the sample design as “randomized and double-blind.” Describe the meaning of “randomized” and “double-blind” in the context of this study.
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The article “Treadmill Exercise and Resistance Training in Patients With Peripheral Arterial Disease With and Without Intermittent Claudication. A Randomized Controlled Trial” (M. McDermott, P. Ades, et al., Journal of the American Medical Association, 2009:165–174) reported the results of a study to determine whether treadmill exercise could improve the walking ability of patients suffering from claudication, which is pain caused by insufficient blood flow to the muscles of the legs. A sample of 48 patients walked on a treadmill for six minutes every day. After six months, the mean distance walked in six minutes was 348 m, with a standard deviation of 80 m. For a control group of 46 patients who did not walk on a treadmill, the mean distance was 309 m with a standard deviation of 89 m. Find a 95% confidence interval for the difference in mean distance walked between the two groups of patients.
The article “Treadmill Exercise and Resistance Training in Patients With Peripheral Arterial Disease With and Without Intermittent Claudication. A Randomized Controlled Trial” (M. McDermott, P. Ades, et al., Journal of the American Medical Association, 2009:165–174) reported the results of a study to determine whether treadmill exercise could improve the walking ability of patients suffering from claudication, which is pain caused by insufficient blood flow to the muscles of the legs. A sample of 48 patients walked on a treadmill for six minutes every day. After six months, the mean distance walked in six minutes was 348 meters, with a standard deviation of 80 m. For a control group of 46 patients who did not walk on a treadmill, the mean distance was 309 m with a standard deviation of 89 m. Can you conclude that the mean distance walked for patients using a treadmill is greater than the mean for the controls? Use the α = 0.05 level of significance.
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a. Obtain individual normal probability plots and the standard deviations of the samples.
b. Perform a residual analysis.
c. Use your results from parts (a) and (b) to decide whether conducting a one-way ANOVA test on the data is reasonable. If so, also do parts (d) and (e).
d. Use a one-way ANOVA test to decide, at the 5% significance level, whether the data provide sufficient…
Chapter 1 Solutions
Elementary Statistics (13th Edition)
Ch. 1.1 - Online Medical Info USA Today posted this question...Ch. 1.1 - Reported Versus Measured In a survey of 1046...Ch. 1.1 - Statistical Significance Versus Practical...Ch. 1.1 - Correlation One study showed that for a recent...Ch. 1.1 - Consider the Source. In Exercises 58, determine...Ch. 1.1 - Consider the Source. In Exercises 58, determine...Ch. 1.1 - Consider the Source. In Exercises 58, determine...Ch. 1.1 - Consider the Source. In Exercises 58, determine...Ch. 1.1 - Sampling Method. In Exercises 912, determine...Ch. 1.1 - Sampling Method. In Exercises 912, determine...
Ch. 1.1 - Sampling Method. In Exercises 9-12, determine...Ch. 1.1 - Sampling Method. In Exercises 912, determine...Ch. 1.1 - Statistical Significance and Practical...Ch. 1.1 - Statistical Significance and Practical...Ch. 1.1 - Statistical Significance and Practical...Ch. 1.1 - Statistical Significance and Practical...Ch. 1.1 - In Exercises 1720, refer to the sample of body...Ch. 1.1 - In Exercises 1720, refer to the sample of body...Ch. 1.1 - In Exercises 1720, refer to the sample of body...Ch. 1.1 - In Exercises 1720, refer to the sample of body...Ch. 1.1 - In Exercises 2124, refer to the data in the table...Ch. 1.1 - In Exercises 2124, refer to the data in the table...Ch. 1.1 - In Exercises 2124, refer to the data in the table...Ch. 1.1 - In Exercises 2124, refer to the data in the table...Ch. 1.1 - Whats Wrong? In Exercises 2528, identify what is...Ch. 1.1 - Whats Wrong? In Exercises 2528, identify what is...Ch. 1.1 - Whats Wrong? In Exercises 2528, identify what is...Ch. 1.1 - Whats Wrong? In Exercises 25-28, identify what is...Ch. 1.1 - Workplace Attire In a survey conducted by Opinion...Ch. 1.1 - Checking Job Applicants In a study conducted by...Ch. 1.1 - Marriage Proposals In a survey conducted by...Ch. 1.1 - Chillax USA Today reported results from a Research...Ch. 1.1 - Percentages in Advertising An ad for Big Skinny...Ch. 1.1 - Percentages in Advertising Continental Airlines...Ch. 1.1 - Percentages In Advertising A New York Times...Ch. 1.1 - Percentages in Negotiations When the author was...Ch. 1.1 - Whats Wrong with This Picture? The Newport...Ch. 1.1 - Falsifying Data A researcher at the...Ch. 1.2 - Parameter and Statistic In a Harris Interactive...Ch. 1.2 - Quantitative/Categorical Data Identify each of the...Ch. 1.2 - Discrete/Continuous Data Which of the following...Ch. 1.2 - Health Survey In a survey of 1020 adults in the...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 512, identify whether the given value...Ch. 1.2 - In Exercises 1320, determine whether the data are...Ch. 1.2 - In Exercises 1320, determine whether the data are...Ch. 1.2 - In Exercises 13-20, determine whether the data are...Ch. 1.2 - In Exercises 13-20, determine whether the data are...Ch. 1.2 - In Exercises 1320, determine whether the data are...Ch. 1.2 - In Exercises 1320, determine whether the data are...Ch. 1.2 - In Exercises 1320, determine whether the data are...Ch. 1.2 - In Exercises 1320, determine whether the data are...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2128, determine which of the four...Ch. 1.2 - In Exercises 2932, identify the level of...Ch. 1.2 - Social Security Numbers As part of a project in a...Ch. 1.2 - Temperatures As this exercise is being written, it...Ch. 1.2 - College Ranks As of this writing, U.S. News World...Ch. 1.2 - Countable For each of the following, categorize...Ch. 1.3 - Back Pain Treatment In a study designed to test...Ch. 1.3 - Blinding What does it mean when we say that the...Ch. 1.3 - Replication In what specific way was replication...Ch. 1.3 - Sampling Method The patients included in the study...Ch. 1.3 - Exercises 58 refer to the study of an association...Ch. 1.3 - Experiment or Observational Study Is the study an...Ch. 1.3 - Exercises 58 refer to the study of an association...Ch. 1.3 - Sampling Method Assume that the population...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - In Exercises 920, identify which of these types of...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - Critical Thinking: Whats Wrong? In Exercises 2128,...Ch. 1.3 - In Exercises 2932, indicate whether the...Ch. 1.3 - Prob. 30BSCCh. 1.3 - In Exercises 2932, indicate whether the...Ch. 1.3 - In Exercises 2932, indicate whether the...Ch. 1.3 - In Exercises 3336, identify which of these designs...Ch. 1.3 - In Exercises 3336, identify which of these designs...Ch. 1.3 - In Exercises 3336, identify which of these designs...Ch. 1.3 - In Exercises 3336, identify which of these designs...Ch. 1.3 - Simple Random Sample vs. Random Sample Refer to...Ch. 1 - Hospitals In a study of births in New York State,...Ch. 1 - Hospitals Which of the following best describes...Ch. 1 - Birth Weights In the same study cited in Exercise...Ch. 1 - Birth Weights Are the birth weights described in...Ch. 1 - Birth Weights Which of the following best...Ch. 1 - Statistic /Parameter In an AARP survey of 1019...Ch. 1 - AARP Survey Refer to the survey described in...Ch. 1 - Observational Study or Experiment Are the data...Ch. 1 - Physicians Health Study In the Physicians Health...Ch. 1 - Sampling In a statistical study, which of the...Ch. 1 - Whats Wrong? In an American Optometric Association...Ch. 1 - Paying for First Dates USA Today posted this...Ch. 1 - Sample Design Literacy In Cardiovascular Effects...Ch. 1 - Divorces and Margarine One study showed that there...Ch. 1 - Simple Random Sample Which of the following is/are...Ch. 1 - Defense of Marriage Act Both of the following...Ch. 1 - Colleges in United States Currently, there are...Ch. 1 - Percentages a. The labels on U-Turn protein energy...Ch. 1 - Types of Data In each of the following, identify...Ch. 1 - Statistical Significance and Practical...Ch. 1 - Prob. 1CRECh. 1 - Prob. 2CRECh. 1 - Tallest Person Robert Wadlow (19181940) is the...Ch. 1 - Body Temperature The given expression is used for...Ch. 1 - Determining Sample Size The given expression is...Ch. 1 - Standard Deviation One way to get a very rough...Ch. 1 - Standard Deviation The standard deviation is an...Ch. 1 - Standard Deviation The given expression is used to...Ch. 1 - Scientific Notation. In Exercises 912, the given...Ch. 1 - Scientific Notation. In Exercises 912, the given...Ch. 1 - Scientific Notation. In Exercise 912, the given...Ch. 1 - Prob. 12CRECh. 1 - Prob. 1TPCh. 1 - Critical Thinking: Do Male Symphony Conductors...Ch. 1 - Critical Thinking: Do Male Symphony Conductors...Ch. 1 - Critical Thinking: Do Male Symphony Conductors...Ch. 1 - Critical Thinking: Do Male Symphony Conductors...
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