A researcher conducts an independent-measures study comparing two treatments and reports the t statistic as t(18) = 2.15. a. How many individuals participated in the entire study? b. Using a...

A researcher conducts an independent-measures study comparing two treatments and reports the t statistic as t(18) = 2.15.

a. How many individuals participated in the entire study?

b. Using a two-tailed test with a = 05, is there a significant difference between the two treatments?

c. Compute r²
to measure the percentage of variance accounted for by the treatment effect.