The differences of the two methods are what researches look at when trying to decide what method would be the best for their application. The experimental method allows the researcher to be completely objective, while the questions in a survey may not be phrased quite as objectively. Often, researches want to get "real world" information. In a case like this, the survey method would be a much better choice. Because of the experimental method's artificial setting, the results may not reflect what would happen in the "real world." With a hypothesis that frustration leads to aggressive behavior, the experimental method would probably show the best, most accurate results.
The independent variable is the factor that is being changed and tested by the investigator. The independent variable in the aggressive behavior experiment would be whether or not the sample or subject is frustrated.
The dependent variable is the factor being measured by the investigator. In this experiment, the investigator could put the subject through a frustrating task (manipulating the independent variable); the investigator would then measure the difference in the amount of aggression in the person when he/she was frustrated and when he/she was calm. Thus, the dependent variable would be the measure of the amount of aggression the subject had.
The control is the subject that has had the independent variable withheld. The best control for this experiment would be to have the same person in a calm state. If the same...