a. In testing one mean, the value of what parameter is stated in the null and alternative hypotheses?
b. In testing one mean, what is implied by the null and alternative hypotheses?
Â c. Why are non-directional (two-tailed) rather than directional (one-tailed) alternative hypotheses predominantly used in research studies?
Â d. What are the similarities and differences between the formula for the z-score (Chapter 5) and the z-test for one mean?
e. Under what conditions would one calculate the population standard error of the mean rather than the standard error of the mean?
Â f. What two factors influence the amount of variability in a distribution of sample means?