Films were controlled to be equally arousing. 3. practice is the confound 4.
Ecological validity refers to how the participant, situation, and task interact.
Psychology majors may not be a representative sample for all experimental situations. Students often have prior knowledge of deception, know the expectations for many tasks, and are of a restricted range of ages. Correlation does not imply causation because you are never certain if you are observing a causal relationship or one that is due to a third variable. For instance, in examining how smoking causes lung cancer, there are also effects of pollution and radon to be accounted for. First, have a baseline period in which you measure the number of things the dog trashes.