Latona did an experiment at a military barracks over the space of a few months to examine the effect of group size on group morale.He randomly assigned soldiers to the experimental and control groups and did a pretest and posttest.Midway through the experiment,some of the soldiers were re-assigned to different stations across the U.S.causing the sample size to drop.Which source of internal invalidity does this example reflect?
A)history
B)maturation
C)instrumentation
D)selection biases
E)mortality

Question

Quizplus · Accepted Answer

This example reflects mortality, as the loss of participants due to re-assignment impacted the sample size and potentially the representativeness of the remaining participants.

Latona Did an Experiment at a Military Barracks Over the Space