Question 1) You wish to conduct an ANOVA (one way/omnibus). In order to insure you have enough power to detect differences in your sample, you need to run a power analysis in G*Power. Assume that you are expecting a medium effect size, α = 0.05, and a minimum power of 0.80. Your experiment utilizes three (3) groups. What is the required sample size (a priori)? How many data points should exist in each group?
Question 2) You conducted a Chi-Square Goodness of Fit Test. Unfortunately, you did not get the sample size you had hoped for during your research. You were able to get 55 in the sample. Calculate your actual power (post hoc). You did a 2 X 2 table. Assume you had a medium effect size.
Question 3) You conducted a t-test. You found a statistically significant difference between your groups even though your sample size was relatively small. Upon conducting a post hoc power analysis you found that your actual power was 0.65. What should you do? Is there a problem with having a power less than 0.80 when you have significant differences?
Question 4) You conducted a t-test. You did not find a statistically significant difference between your groups even though your sample size was relatively small. Upon conducting a post hoc power analysis you found that your actual power was 0.57. What should you do? Is there a problem with having a power less than 0.80 when you do not have significant differences?