A sleep researcher is studying the effect of sleep deprivation on cognitive abilities. In his most recent study, one group of participants was kept awake all night and another group was allowed to sleep comfortably. Both groups were subsequently given a basic math test to see how many problems could be solved within a 5-minute period of time. Scores for both groups are listed below. The researcher believes that the sleep deprived participants will solve fewer problems.

Sleep Deprived Not Sleep Deprived

6 12

10 14

8 11

4 17

11 14

9 10

a.Conduct an independent samples t test with a = .01.

b.Determine and interpret the effect size.