A selection bias occurs when
A) researchers use a different version of the dependent measure at the posttest than at the pretest.
B) research participants in the control condition of an experiment differ in some way from the participants in the experimental condition.
C) the dependent variable in a study is assessed by having research participants choose between performing two or more behaviors.
D) researchers choose one operational definition of a dependent variable over another rather than using multiple operational definitions.

Question

Quizplus · Accepted Answer

A selection bias occurs when the participants in a study are not randomly assigned to groups, which means that participants in the control condition of an experiment differ in some way from the participants in the experimental condition. This can lead to confounding variables and affect the validity of the results. The other options describe different issues that can affect the measurement or operationalization of the dependent variable, but they do not relate specifically to selection bias.

A Selection Bias Occurs When