Author Question: A researcher wants a 90 percent chance of rejecting the null hypothesis at the one-tailed .05 level ... (Read 40 times)

dakota nelson · **on:** Jun 20, 2018

A researcher wants a 90 percent chance of rejecting the null hypothesis at the one-tailed .05 level with an effect size of .15 . The sample size needed is about

a. 140.
b. 160.
c. 180.
d. 200.
e. 380

Question 2

The greatest statistical power occurs when

a. the sample is small and heterogeneity is small.
b. the sample is small and heterogeneity is large.
c. the sample is large and heterogeneity is small.
d. the sample is large and heterogeneity is large.