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 19P
Problem 18 shows that removing individual differences can substantially reduce variance and lower the standard error. However, this benefit only occurs if the individual differences are consistent across treatment conditions. In problem 18, for example, the first two participants (top two rows) consistently had the highest scores in both treatment conditions. Similarly, the last two participants consistently had the lowest scores in both treatments. To construct the following data, we started with the scores in problem 18 and scrambled the scores in treatment 1 to eliminate the consistency of the individual differences.
- a. Assume that the data are from an independent-measures study using two separate samples, each with n = 6 participants. Compute the pooled variance and the estimated standard error for the
mean difference. - b. Now assume that the data are from a repeated measures study using the same sample of n = 6 participants in both treatment conditions. Compute the variance for the sample of difference scores and the estimated standard error for the mean difference. (This time you should find that removing the individual differences does not reduce the variance or the standard error.)
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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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