A researcher wants to know whether wearing sunglasses improves driving performance.If an independent groups design is used,the researcher would manipulate the variable by
A) randomly assigning half the drivers to a sunglasses condition and half to a no-sunglasses condition.
B) having all drivers first drive without sunglasses and then with sunglasses.
C) having half the drivers first drive without sunglasses and then with sunglasses and having the other half first drive with sunglasses and then without sunglasses.
D) selectively placing half the drivers to a sunglasses condition and half to a no-sunglasses condition.

Question

Quizplus · Accepted Answer

In an independent groups design, the researcher manipulates the independent variable by randomly assigning participants to either the experimental or control group. In this case, the independent variable is wearing sunglasses, so the researcher would randomly assign half the participants to wear sunglasses and the other half to not wear sunglasses. This allows for a comparison between the two groups and for the researcher to determine whether or not wearing sunglasses improves driving performance. Options B and C both involve having all participants experience both conditions, which would not allow for a comparison between groups. Option D is not a method of random assignment and therefore may introduce bias.

A Researcher Wants to Know Whether Wearing Sunglasses Improves Driving