Exhibit 10-10: Identify the major threat to internal validity in the following research studies.
-Refer to Exhibit 10-10.A researcher conducted a semester-long experiment comparing two instructional programs in math.During the administration of tests during the semester, the researcher found that about ten percent of the experimental group and about five percent of the control group were absent for each administration.
A) Regression
B) Diffusion
C) Mortality
D) Selection
E) History

Question

Quizplus · Accepted Answer

The major threat to internal validity in this study is mortality, as there was differential attrition (absenteeism) between the experimental and control groups. This could potentially bias the results if the students who were absent had different levels of math ability or different levels of motivation to learn math. The other threats to internal validity (regression, diffusion, selection, and history) are less relevant to this particular study.

Exhibit 10-10: Identify the Major Threat to Internal Validity in the Following