Categorical variables included in the statistical analysis of experimental data as a way of statistically controlling or accounting for variance due to that variable are called _____ variables.
A) independent
B) dependent
C) blocking
D) covariate

Question

Quizplus · Accepted Answer

Blocking variables are used in experimental design to control for sources of variation that might otherwise mask the effects of the treatments being tested. They are not independent variables, because they are not being manipulated by the experimenter, nor are they dependent variables, because they are not being measured as outcomes. Covariate variables, on the other hand, are related to the dependent variable of interest, and are included in the analysis to account for their effects on the outcome.

Categorical Variables Included in the Statistical Analysis of Experimental Data