A health psychologist conducts an experiment to test the effectiveness of four techniques for helping a person to relax.The psychologist has a limited number of people available to participate in the experiment and each relaxation technique takes some time to complete.The psychologist has decided,therefore,to use the incomplete repeated measures design with all possible orders to balance practice effects.What is the minimum number of participants the psychologist will need for this experiment?
A) 4
B) 12
C) 24
D) 48

Question

Quizplus · Accepted Answer

The incomplete repeated measures design with all possible orders involves testing each participant in a different order of techniques to balance out any potential practice effects. With four techniques, there are 4! (4 factorial) possible orders.

4! = 4 x 3 x 2 x 1 = 24

Therefore, to have all possible orders with at least one participant for each order, the minimum number of participants needed is 24.

A Health Psychologist Conducts an Experiment to Test the Effectiveness