Repeatedly dividing the sample on the basis of demographic descriptors to look for differences in the means of outcome variables for different subgroups of the sample
A) raises the chances of a Type I error.
B) raises the chances of hindsight error.
C) lowers the internal validity of a study.
D) increases the level of external validity.

Question

Quizplus · Accepted Answer

Repeatedly dividing the sample on the basis of demographic descriptors increases the number of groups being compared and therefore raises the chances of a Type I error (rejecting the null hypothesis when it is true). This is known as the multiple comparison problem.

Repeatedly Dividing the Sample on the Basis of Demographic Descriptors