ABSTRACT
Although the experiment is the only research strategy that can determine if one variable causes another, not all phenomena of interest to behavioral scientists can be studied experimentally. For example, it is impossible to manipulate some factors, such as personality, that behavioral scientists would like to study as independent variables. If manipulation is not possible, then neither is experimentation. In other cases, it might be unethical to manipulate a variable. For example, researchers might want to conduct an experimental study of the effects of long-term exposure to severe stress. Although such an experiment would be possible, it would raise ethical concerns about harm to the participants.
