If groups in two different workplaces are studied to see how changes in working conditions affect output, those in one workplace may experience events not related to the independent variable but that affect the dependent variable.
The threat to internal validity here is
a. selection.
b. maturation.
c. statistical regression.
d. history.
Question 2
When psychologists test mice in their research, some of the mice may die during the course of a study because these animals have a short lifespan. The threat to internal validity of the data here is
a. selection.
b. maturation.
c. subject mortality.
d. history.