In which experimental design is a single,categorical extraneous variable that might affect test units' responses to the treatment identified and the effects isolated by being blocked out?
A)completely randomized design
B)randomized-block design
C)factorial design
D)interactive block design

Question

Quizplus · Accepted Answer

In a randomized-block design, the extraneous variable is identified and controlled by blocking it out, meaning that it is thoroughly studied to see how it affects the outcome. This allows the treatment to be given to each block, ensuring that the results are not skewed by the extraneous variable. Therefore, the best choice is B.

In Which Experimental Design Is a Single,categorical Extraneous Variable That