A researcher wants to find out how much fins increase swimming speed.If an independent groups design is used,the researcher would manipulate the variable by
A) randomly assigning half the swimmers to the no-fin condition and half to the fin condition.
B) having all swimmers first swim without fins,then swim with fins.
C) having half the swimmers first swim without fins and then with fins,and having the other half swim first with fins and then without fins.
D) having some swimmers swim with fins,some swimmers swim with only one fin,and some swimmers swim with no fins.

Question

Quizplus · Accepted Answer

In an independent groups design, participants are randomly assigned to either the experimental or control group. Therefore, the best choice for manipulating the variable would be to randomly assign half of the swimmers to the fin condition and half to the no-fin condition. This ensures that any differences in swimming speed can be attributed to the fins and not to any other confounding variable. Options B, C, and D do not involve random assignment or control groups, and may introduce extraneous variables that could impact the results.

A Researcher Wants to Find Out How Much Fins Increase