Using a repeated measures design, Researcher A computes the following test statistic, t(22) = 1.980, and decides to reject the null hypothesis. Using a matched samples design, Researcher B computes the same test statistic, t(22) = 1.980, but decides to retain the null hypothesis. Which of the follow can explain why this occurred?

  1. (a) The repeated measure design is a more powerful design than the matched samples design
  2. (b) Researcher A computed a one-tailed test; Researcher B computed a two-tailed test
  3. (c) Researcher A used a .05 level of significance; Researcher B used a .10 level of significance