Which of the following would be an example of selection bias?
A) volunteers
B) random assignment to experimental and control groups
C) matching on experimental and comparison groups
D) making sure that the quotas are the same for the experimental and comparison groups with respect to important variables

Question

Quizplus · Accepted Answer

Selection bias occurs when the individuals or items in a study are not chosen randomly or have unequal probabilities of being selected. Volunteers are self-selecting and may differ in important ways from the larger population, leading to selection bias. Random assignment to groups (B), matching (C), and quota sampling (D) are methods used to reduce or eliminate selection bias.

Which of the Following Would Be an Example of Selection