Answer:
the Hawthorne effect
Step-by-step explanation:
In conducting an experiment on prison violence, researchers randomly placed cameras in certain cells. The results showed unusually low incidents of conflict between prisoners in areas where cameras were present. This change in the prisoners' behavior as a result of being observed is known as the Hawthorne effect.
The Hawthorne Effect is the tendency for people who are the subjects of an experimental study to make positive adjustment to their behavior that is being evaluated only because it is being studied and not because of changes in the experiment parameters or stimulus.
In this case the prisoners adjusted their behavior because of the presence of cameras not for any other reason.