A statistics tutor wants to assess whether her remedial tutoring has been effective for her five students. Using a pre-post design, she records the following grades for a group of students prior to and after receiving her tutoring.
Tutoring
Before ____________________________ After
2.4 ..................................................3.0
2.5 ..................................................2.8
3.0 ..................................................3.5
2.9 ..................................................3.1
2.7 ..................................................3.5
(a) Test whether or not her tutoring is effective at a .05 level of significance. State the value of the test statistic and the decision to retain or reject the null hypothesis.
(b) Compute effect size using estimated Cohen's d.