Threats to Internal Validity Which threat to internal validity exists in each of the situations listed below? Column A: Situation Column B: Threat to Internal 'Valid' 1. A researcher wishes to compare . Maturation changes in achievement motivation of - Mortality males and females during their high . Data collector characteristics school years- [hiring her study, she Location discovers that more males than . Instrumentation females failed to complete high . Regression school. . Two groups of students are compared with regardtotheir attitude towarda career in the military. Two different: recruiting officers administer the same attitude scale to each group. The recruiter who administers the scale to the rst group is in uniform; the second recruiter is in civilian clothes. . Those studentswho score iuthetop 2 percent on ahiologytlsthave, on average, lower scores the second time they talre the test. . A researcher wants to measure changes in student attitudes toward their graduate programs at a local tmiversity. He nds a questionnaire used by another researcher the previous year that aslrs most of the questions he wants to aslr. To improve it, he changes some of the questions and adds a few more. . A researcher observes level of attention in a special program during the month of September and again in May- . A researcher interviews two groups of individuals. Clue group is interviewed in his classroom; the other group, although asked the same questions, is interviewed in the student union