When,from the outset of a study,differences exist between the kinds of individuals in one group of an experiment and those in another,there is a potential threat to internal validity called
A)selection.
B)maturation.
C)additive effect of selection and history.
D)contamination.

Question

Quizplus · Accepted Answer

The potential threat to internal validity in this scenario is selection. The reason is that if the individuals in one group are different from those in another group at the beginning of the study, it may be difficult to attribute any observed differences between the groups to the independent variable (the variable being manipulated in the study) rather than to pre-existing differences between the groups.

When,from the Outset of a Study,differences Exist Between the Kinds