Introduction to Statistics and Data Analysis
5th Edition
ISBN: 9781305445963
Author: PECK
Publisher: Cengage
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Chapter 11.3, Problem 56E
Women diagnosed with breast cancer whose tumors have not spread may be faced with a decision between two surgical treatments—mastectomy (removal of the breast) or lumpectomy (only the tumor is removed). In a long-term study of the effectiveness of these two treatments, 701 women with breast cancer were randomly assigned to one of two treatment groups. One group received mastectomies and the other group received lumpectomies and radiation. Both groups were followed for 20 years after surgery. It was reported that there was no statistically significant difference in the proportion surviving for 20 years for the two treatments (Associated Press, October 17, 2002).
What hypotheses do you think the researchers tested in order to reach the given conclusion?
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Chapter 11 Solutions
Introduction to Statistics and Data Analysis
Ch. 11.1 - Consider two populations for which 1 = 30, 1 = 2,...Ch. 11.1 - An individual can take either a scenic route to...Ch. 11.1 - Prob. 3ECh. 11.1 - Prob. 4ECh. 11.1 - The article Plugged In, but Tuned Out (USA TODAY,...Ch. 11.1 - Prob. 6ECh. 11.1 - Prob. 7ECh. 11.1 - The paper If Its Hard to Read, Its Hard to Do...Ch. 11.1 - Is injecting medical cement effective in reducing...Ch. 11.1 - Prob. 10E
Ch. 11.1 - Prob. 11ECh. 11.1 - The paper Mood Food: Chocolate and Depressive...Ch. 11.1 - Prob. 13ECh. 11.1 - Example 11.1 looked at a study comparing students...Ch. 11.1 - Prob. 15ECh. 11.1 - Prob. 16ECh. 11.1 - A newspaper story headline reads Gender Plays Part...Ch. 11.1 - Prob. 18ECh. 11.1 - Fumonisins are environmental toxins produced by a...Ch. 11.1 - A researcher at the Medical College of Virginia...Ch. 11.1 - Do certain behaviors result in a severe drain on...Ch. 11.2 - Suppose that you were interested in investigating...Ch. 11.2 - Head movement evaluations are important because...Ch. 11.2 - To determine if chocolate milk was as effective as...Ch. 11.2 - The humorous paper Will Humans Swim Faster or...Ch. 11.2 - The study described in the paper Marketing Actions...Ch. 11.2 - Prob. 27ECh. 11.2 - The paper Less Air Pollution Leads to Rapid...Ch. 11.2 - The paper The Truth About Lying in Online Dating...Ch. 11.2 - Prob. 30ECh. 11.2 - Prob. 31ECh. 11.2 - The paper Quantitative Assessment of Glenohumeral...Ch. 11.2 - Two proposed computer mouse designs were compared...Ch. 11.2 - Prob. 34ECh. 11.2 - Prob. 35ECh. 11.2 - The authors of the paper Ultrasound Techniques...Ch. 11.3 - Some people seem to believe that you can fix...Ch. 11.3 - Prob. 38ECh. 11.3 - After the 2010 earthquake in Haiti, many...Ch. 11.3 - Prob. 40ECh. 11.3 - The report Audience Insights: Communicating to...Ch. 11.3 - Prob. 42ECh. 11.3 - Prob. 43ECh. 11.3 - Prob. 44ECh. 11.3 - The article Fish Oil Staves Off Schizophrenia (USA...Ch. 11.3 - The report Young People Living on the Edge...Ch. 11.3 - Prob. 47ECh. 11.3 - Prob. 48ECh. 11.3 - Prob. 49ECh. 11.3 - Prob. 50ECh. 11.3 - Prob. 51ECh. 11.3 - The article Spray Flu Vaccine May Work Better Than...Ch. 11.3 - Prob. 53ECh. 11.3 - The following quote is from the article Canadians...Ch. 11.3 - Prob. 55ECh. 11.3 - Women diagnosed with breast cancer whose tumors...Ch. 11.3 - Prob. 57ECh. 11.4 - The paper The Psychological Consequences of Money...Ch. 11.4 - An experiment to determine if an online...Ch. 11.4 - The paper Ready or Not? Criteria for Marriage...Ch. 11 - Prob. 61CRCh. 11 - Prob. 62CRCh. 11 - A deficiency of the trace element selenium in the...Ch. 11 - Prob. 64CRCh. 11 - Prob. 65CRCh. 11 - In a study of a proposed treatment for diabetes...Ch. 11 - When a surgeon repairs injuries, sutures (stitched...Ch. 11 - Prob. 68CRCh. 11 - In a study of memory recall, eight students from a...Ch. 11 - As part of a study to determine the effects of...Ch. 11 - Prob. 71CRCh. 11 - Prob. 72CRCh. 11 - The article Truth and DARE: Tracking Drug...Ch. 11 - The article Softball Sliding Injuries (American...Ch. 11 - Prob. 75CRCh. 11 - Wayne Gretzky was one of ice hockeys most prolific...Ch. 11 - Heres one to sink your teeth into: The authors of...Ch. 11 - Prob. 78CRCh. 11 - Dentists make many people nervous. To see whether...Ch. 11 - Prob. 80CRCh. 11 - Prob. 81CRCh. 11 - Both surface soil and subsoil specimens were taken...
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