Question

differences can substantially enefit only occurs if the Pla We 6:00 reduce variance and lower the standard error. However, thi individual differences are consistent across treatment conditions. In problem 21, for example, the particlpants with the highest scores in the more-sleep condition also had the Mini Wec 6:00 sche apol inco highest scores in the less-sleep condition. Similarly, participants with the the first condition also had the lowest scores in the second condition. To construct the st scores in following data, we started with the scores in problem 21 and scrambled the scores in treatment 1 to eliminate the consistency of the Individual differences. Number of Academic Problems Student Following Following Nights with Nights with Above Below Average Sleep Average Sleep A 10 13 14 5 C 13 5 5 E 9 6 10 11 3 6 H a. Treat the data as if the scores are from an independent-measures study using two separate samples, each withn 8 participants. Compute the pooled varlance, the estimated standard error for the mean difference, and the independent-measurest statistic. Using a two-talled test with a 05, is there a significant difference between the two sets of scores? Note: The scores in each treatment are the same as in Problem 21. Nothing has changed. b. Now assume that the data are from a repeated-measures study using the same sample of n 8 participants in both treatment conditions. Compute the variance for the sample of difference scores, the estimatted standard eror for the mean difference and ,05, is there a the repeated-measures t statistic, Usine a two-talled test with a significant difference between the two sets of scores? (You should find that removing the individual differences with a repeated-measures r no longer reduces the variance because there are no consistent individual differences)

Answer 1

Solution:

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