Question to test your Two Means - Matched Pairs (Dependent Samples) knowledge

Question

A psychologist is studying the effect of a stress management workshop on anxiety levels. Eight participants took an anxiety test before and after attending the workshop. Their scores are as follows:

a. Using a $0.01$ significance level, test the claim that the mean anxiety score before the workshop is higher than after the workshop.
b. Construct the $99 percent sign$ confidence interval for the mean difference. What does this interval indicate about anxiety change?
c. What can you conclude about the effectiveness of the workshop?

Accepted Answer

Test statistic t=23.01 t = 23.01 , critical value t0.01,7=2.998 t_{0.01, 7} = 2.998 99%99\% confidence interval: 2.44μd3.31 2.44 The workshop significantly reduced anxiety levels

Answer

Test statistic t=1.85 t = 1.85 , critical value t0.01,7=2.998 t_{0.01, 7} = 2.998 99%99\% confidence interval: −0.11μd1.07 -0.11 There is no significant evidence that the workshop reduced anxiety

Answer

Test statistic t=23.01 t = 23.01 , critical value t0.01,7=2.998 t_{0.01, 7} = 2.998 99%99\% confidence interval: −3.31μd−2.44 -3.31 The workshop significantly increased anxiety levels

Answer

Test statistic t=2.44 t = 2.44 , critical value t0.01,7=3.31 t_{0.01, 7} = 3.31 99%99\% confidence interval: 0.87μd4.01 0.87 There is weak evidence the workshop had an effect on anxiety

Two Means - Matched Pairs (Dependent Samples): Videos & Practice Problems