Introductory Statistics (2nd Edition)
2nd Edition
ISBN: 9780321978271
Author: Robert Gould, Colleen N. Ryan
Publisher: PEARSON
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Textbook Question
Chapter 2, Problem 71CRE
Changing Multiple-Choice Answers When Told to Do So One of the authors wanted to determine the effect of changing answers on multiple-choice tests. She had advised her students that if they had changed their minds about a previous answer, they should replace their first choice with their new choice. By looking for erasures on the exam, she was able to count the number of changed answers that went from wrong to right, from right to wrong, and from wrong to wrong. The results are shown in the bar chart.
a. Do the data support her view that it is better to replace your initial choice with the revised choice?
b. Compare this bar chart with the one in Exercise 2.37. Does changing answers generally tend to lead to higher or to lower grades?
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Chapter 2 Solutions
Introductory Statistics (2nd Edition)
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