After 30 years of teaching the same research methods course, Professor Zone's average exam scores increase because he doesn't want to spend the time arguing with students over borderline grades. This is an example of:
A) History effect
B) Instrumental decay
C) Mortality
D) Differential attrition
E) Contamination

Question

Quizplus · Accepted Answer

This situation fits the definition of instrumental decay, which occurs when the effect of the treatment weakens over time and the instrument becomes less effective. In this case, Professor Zone's approach of giving borderline students higher grades is a form of treatment, and over time he has weakened the effectiveness of the grading system, leading to higher average scores.

After 30 Years of Teaching the Same Research Methods Course