Worker productivity is assessed before and after a program for flextime is instituted. Just after the pretest, workers receive an unexpected bonus check based on unusually high product sales. Productivity is higher on the posttest than on the pretest, but the researcher suspects ______ as a threat to internal validity.
A)history
B)regression
C)instrumentation
D)selection

Question

Quizplus · Accepted Answer

The unexpected bonus check represents a historical event that could have influenced the workers' productivity, making it a threat to internal validity by potentially causing the observed increase in productivity rather than the flextime program itself.

Worker Productivity Is Assessed Before and After a Program for Flextime