In an experiment investigating the hypothesis that aerobic exercise improves concentration and memory, all the participants had an equal chance of being assigned to any of the three conditions in the study. The researchers have used _____ to minimize the possibility of bias when assigning participants to the different groups.
A)the practice effect
B)random assignment
C)the single-blind technique
D)the double-blind technique

Question

Quizplus · Accepted Answer

Random assignment is the process of assigning participants to different groups in a way that every participant has an equal chance of being assigned to any of the groups. This method helps to minimize the possibility of bias when assigning participants to the different groups. As a result, it strengthens the internal validity of the study. Therefore, option B is the correct answer. The practice effect refers to the improvement in performance that results from repeated exposure to the same task. The single-blind technique is a research method in which the participants are unaware of the group assignment, while the double-blind technique is a research method in which both the participants and the researchers are unaware of the group assignments. However, these techniques are not directly related to the minimization of bias during the assignment of participants to groups.

In an Experiment Investigating the Hypothesis That Aerobic Exercise Improves