Jay Weiss, a psychologist, used electric shock on rats in a control group and rats in an experimental group. One group; however, was given a piece of wood to chew on. They had fewer ulcers (open sores or lesions in stomach lining).
What is the independent variable and dependent variable?
see other post. Jay is not a nice animal lover.
An independent variable is the potential stimulus or cause, usually directly manipulated by the experimenter, so it could also be called a manipulative variable.
A dependent variable is the response or measure of results.