Which experimental design means that two groups of test units were randomly assigned to two different treatment groups at the same time,and the dependent variable was measured in the two groups simultaneously?
A) X O1 O2
X O1 O2
B) R X1 O1
O2 X2 O2
C) R X1 O1
R X1 O1
D) R X1 O1
R X2 O2

Question

Quizplus · Accepted Answer

In design D, "R" indicates random assignment, and "X1" and "X2" represent different treatments applied to two groups. "O1" and "O2" are the observations or measurements of the dependent variable taken simultaneously after the treatments.

Which Experimental Design Means That Two Groups of Test Units