RESEARCH STUDY 5.2: Dr. Sheffield is a clinical psychologist who specializes in treating pathological gambling. Pathological gambling is defined as being unable to resist impulses to gamble. Bothered by not having a good measure that he can give to clients to determine whether they are suffering from this condition, he creates a new measure of pathological gambling. The measure has 15 questions, and it takes 20 minutes to complete. Dr. Sheffield has now decided that he wants to test his measure on some university students (who some estimates say have a 6% prevalence rate of compulsive gambling). He has a group of 100 university students complete his measure. He also has them complete two other measures (one that measures addictive behavior in general and one that measures general attitudes toward gambling). He finds that his new measure is positively associated with each of these other measures. This procedure has provided evidence for the ________ of Dr. Sheffield’s measure.