9.a. Which correctly describes an independent-samples T test?

a.it has two sources of variance

b.It uses the same group of participants in all of the treatment conditions being compared.

c.It uses one group of participants to evaluate a hypothesis about one population mean.

d.it has one source of variance

b.

The data from an independent-measures research study produce a sample mean difference of 8 points and an estimated standard error of 2 points.

If there are n = 8 scores in each sample, then your calculatedt statistic is ____.

a.8/4

b.8/0.50

c.8/0.25

d.none of the answers are correct

c. For the repeated-measures t statistic, df = ____.

a.(n₁- 1) + (n₂- 1)

b.n₁+ n₂- 1

c.n₁+ n₂- 2

d.n - 1, where n is the number of pair of scores

d. In an independent groups design

a.we are looking for differences in mean scores,

but we hope that the variances in each group are approximately the same.

b.we calculate the variance from the difference scores

c.we hope the variances in each group are different

d.none of the answers are correct.