PSY475 (Week 1 DQ 2)
Compare and contrast reliability and validity?
Going back to Plato’s cave wall of shadows, if we all held up mirrors and reflected a particular point outside the cave would we all see the same thing and further if we were to take another peek an hour later would we see the same thing (reliability). Second is the subject of validity. My second class at college was a critical thinking class. I loved it. I can remember studying syllogisms: All animals are big, all big things are slow, therefore all animals are slow. This syllogism is valid, but not true (i.e. the conclusion reasonable follows from the premises). The problem with this syllogism is that the premises are untrue. They are both global absolutes, which are almost always false or at the very least not completely true in all instances. It is the same with psychological testing: the conclusion must reasonably flow from the facts gathered during experimentation. It would seem that validity has to do more with the interpretation of test results, than the test results themselves. Referring to the hypothesis as an elucidation of causality, validity is the bridge by which the numerical quantification of numbers is verified as it is translated into causation. It is a hindsight mechanism. It is used to verify the applicability of the test results to the hypothetical conclusion of causation.
Both are equally important I think. If not, then the test might give great scores one time and not the next or the results of a test might be used to reinforce a cause that does not exist or worse yet is poorly supported by the available facts. Furthermore, the aim of both instruments is to over the shadows (i.e. subjectivity and opinion) to see through to the reality outside the cave. Unfortunately, we are all biased by our beliefs, values, and pre-existing inclinations, so measures of validity and