In experimental research, what do we call an individual who acts as a participant but whose behavior is planned in advance?

In experimental research, a confederate is an individual who is part of the research team and acts as though they are a participant, but their behavior is actually scripted and predetermined. Confederates are often used to create specific social situations or to manipulate variables within a study. For example, they may interact with actual participants in ways that test hypotheses about social behavior, perception, or group dynamics.

The use of a confederate allows researchers to maintain control over the experimental conditions while still observing the responses and behaviors of genuine participants in a naturalistic setting. This method can help in gathering data about how individuals react to specific stimuli or scenarios orchestrated by the confederate.