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10. Examine the following decisions researchers have made about their experiment

ID: 3320382 • Letter: 1

Question

10. Examine the following decisions researchers have made about their experiments. Was the correct decision made? If not, did they commit Type I or Type II error? You may want to check to make sure they looked up the correct critical value first. 3 points Test Statistic Obtained by Critical Value Looked Up The Decision They MadeIs the decision correct? the Researchers If not, did they make a Type l or Type Il error You cannot answer no without indicating which tvpe of error also. .05, one-tailed; df= 19 tcrít = 1.729 = .01, two-tailed; df= 20 crit537 Fcrit4.88 t-1.95 Retain the null or Fail to reject the null Reject the null F. (7.11 ) 5.86, = .01 Reject the null

Explanation / Answer

(a) Since t (1.95) is > tcrit (1.729), we should reject H0. The decision taken to retain the null is wrong. This is a Type II error (incorrectly retaining the null when actually it should have been rejected).

(b) The decision to reject the null is correct as r (+0.596) is greater than r crit( +0.537).

(c) The decision to reject the null is correct as F (5.86) is greater than F crit( 4.88).