A researcher conducts a power analysis before implementing a research study to assess the probability of finding a significant effect if it exists. The researcher wants to compare differences between two means on a dependent variable from two independent groups of participants using a one-tailed independentt-test and a total sample size of 70 participants. The following a priori (estimated) effect size, alpha level, estimated sample size, and a criterion power value are used for the power analysis. (1) one-tailed independentt-test (2) a priori (estimated) effect size from a previous study ofd= .45 (3) = .01 (4) criterion power value = .80 (5) 35 participants in each group so allocation ratio is 35/35 = 1

Calculate the power analysis using G*Power 3. 1. 2 as shown in Chapter 3 and identify the correct answer below.

Group of answer choices

b. A total sample size of 202 will be needed to reach an actual power of .8022908 using a one-tailed independent t-test, estimated d = .45, = .01, & criterion power value = .80

a. A total sample size of 101 will be needed to reach an actual power of .8550635 using a one-tailed independent t-test, estimated d = .45, = .01, & criterion power value = .80

c. A total sample size of 150 will be needed to reach an actual power of .8078235 using a one-tailed independent t-test, d = .45, = .01, & criterion power value = .80

d. A total sample size of 98 will be needed to reach an actual power of .9075635 using a one-tailed independent t-test, estimated d = .45, = .01, & criterion power value = .80