TERM I, Module 1 -Exp. Methods: EXPERIMENTS.

METHODS

in Psychology.

EXPERIMENTALand NON - EXPERIMENTAL METHODS.

EXPERIMENTAL METHODS:Experiments.

QuantitativeResearch.

The only way Psychologists can establish cause- and – effect relationships through research is by carrying out an Experiment. In a formal experiment, the researcher investigates the relationship between two (or more) Variables by deliberately changing one Variable in a controlled situation and observing the effects of that change on other aspects of the situation. In an Experiment, then, the conditions are created and controlled by the researcher, who deliberately makes a change in those conditions in order to observe the effects of the change.

The change that the researcher deliberately makes in an Experiment is called Experimental Manipulation. Experimental Manipulations are used to detect relationships between different Variables. Several steps are involved in carrying out an Experiment, but the process typically begins with the development of one or more hypotheses for the Experiment to test.

Independent Variable: The Variable that is manipulated by an experimenter. Dependent Variable: The ariable that is measured and is expected to change as a result of changes caused by the experimenter’s manipulation of the Independent Variable.

Advantages:

Experiments offer the only way to determine cause- and – effect relationships.

Disadvantages:

To be valid, Experiments require random assignment of participants to conditions, well- conceptualized Independent and Dependent Variables, and other careful controls.

One Experiment alone does not forever resolve the question. Psychologists- like other Scientists- require that findings be replicated, or repeated, sometimes using other procedures, in other settings, with other groups of participantes, before full confidence can be placed in the results of any single Experiment.

In addition to replicating experimental results, Psychologists need to test the limitations of their theories and hypotheses to determine under which specific circumstances they do and do not apply. Therefore, it is critical to continue carrying out Experiments to understand the conditions in which exceptions to this general rule occur and other circumstances in which the rule holds.