Essentials of Statistics for the Behavioral Sciences
8th Edition
ISBN: 9781133956570
Author: Frederick J Gravetter, Larry B. Wallnau
Publisher: Cengage Learning
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Chapter 11, Problem 22P
The teacher from Problem 21 also tried a different approach to determining whether changing answers helps or hurts exam grades. In another class, students were told to review their final exams and change any answers and wanted to before turning them in. However, the students had to indicate both the original answer and the changed answer for each question. The teacher graded each exam twice, once using the set of original answers and once with the changes. In the class of n = 22 students, the exam scores improved by an average of MD = 2.5 points with changed answers. The standard deviation for the difference scores was s = 3.1. Are the data sufficient to conclude that rethinking and changing answers can significantly improve scores? Use a one-tailed test at the .01 level of significance.
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Chapter 11 Solutions
Essentials of Statistics for the Behavioral Sciences
Ch. 11.2 - For the following data from a repeated-measures...Ch. 11.2 - Prob. 2LCCh. 11.3 - Prob. 1LCCh. 11.3 - A researcher is investigating the effectiveness of...Ch. 11.3 - Prob. 2LCACh. 11.3 - Prob. 3LCACh. 11.4 - Prob. 1LCCh. 11.4 - Prob. 2LCCh. 11.4 - Prob. 3LCCh. 11 - What is the defining characteristic of a...
Ch. 11 - Participants enter a research study with unique...Ch. 11 - Explain the difference between a matched-subjects...Ch. 11 - A researcher conducts an experiment comparing two...Ch. 11 - A sample of n = 9 individuals participates in a...Ch. 11 - Solve the following problems. a. A...Ch. 11 - Prob. 7PCh. 11 - A sample of difference scores from a...Ch. 11 - When you get a surprisingly low price on a product...Ch. 11 - Research has shown that losing even one night's...Ch. 11 - Prob. 11PCh. 11 - Masculine-themed words (such us competitive,...Ch. 11 - Research results indicate that physically...Ch. 11 - Researchers have noted a decline in cognitive...Ch. 11 - The following data are from a repeated-measures...Ch. 11 - A researcher for a cereal company wanted to...Ch. 11 - Research indicates that the color red increases...Ch. 11 - One of the primary advantages of a...Ch. 11 - Problem 18 shows that removing individual...Ch. 11 - A researcher uses a matched-subjects design to...Ch. 11 - Some evidence suggests that you are likely to...Ch. 11 - The teacher from Problem 21 also tried a different...Ch. 11 - At the Olympic level of competition, even the...Ch. 11 - Example 11.1 in this chapter presented a...Ch. 11 - Belsky, Weinraub, Owen, and Kelly (2001) reported...Ch. 11 - Do you view a chocolate bar as delicious or as...Ch. 11 - Prob. 3RE
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