The mean is defined as the a. range of the data set b. average of a data set. c. middle of the data set. d. number that shows up most often in a data set.

Kilgore trout creates a new scale to diagnose depression. however, his scale only assesses one symptom of depression while ignoring others. which of the following is his new scale most likely lacking? a) test-retest reliability b) discriminant validity c) criterion validity d) alternate-forms reliability e) content validity f) none of the above