If the purpose of a statistic is to report the middle position in one or more distributions, which of the following is the appropriate statistic?

The advantage of a within-subjects design is that

A) the F-ratio is reduced. B) randomized participant assignment is maximized. C) it requires fewer dependent measures. D) it equates participant in conditions prior to experimental manipulation.

If you have conducted a study using the regression-discontinuity design, how would you tell if your treatment had an effect?

a. by looking at the data to see if the regression line of the posttest scores differs from the regression line of pretest scores. b. by statistically analyzing the data using Analysis of Variance. c. by comparing the pretest scores with the posttest scores to see if there was a significant change. d. by determining if there is a discontinuity in the regression line for the people above and below the cutoff score.