Select three of the six important assumptions we must make when using psychological tests. Define the three assumptions in your own words. Provide an example for each assumption.

Question

What will be an ideal response?

Answer 1

Six assumptions:
• Psychological tests measure what they purport to measure or predict what they are intended to predict. In addition, any conclusions or inferences that are drawn about the test takers based on their test scores must be appropriate. This is also called test validity. If a test is designed to measure mechanical ability, we must assume that it does indeed measure mechanical ability. If a test is designed to predict performance on the job, then we must assume that it does indeed predict performance. This assumption must come from a personal review of the test’s validity data.
• An individual’s behavior, and therefore test scores, will typically remain stable over time. This is also called test–retest reliability. If a test is administered at a specific point in time and then we administer it again at a different point in time (e.g., 2 weeks later), we must assume, depending on what we are measuring, that an individual will receive a similar score at both points in time. If we are measuring a relatively stable trait, we should be much more concerned about this assumption. However, there are some traits, such as mood, that are not expected to show high test–retest reliability.
• Individuals understand test items the same way. For example, when asked to respond “true” or “false” to a test item such as “I am almost always healthy,” we must assume that all test takers interpret “almost always” similarly.
• Individuals will report accurately about themselves (e.g., about their personalities, about their likes and dislikes). When we ask people to remember something or to tell us how they feel about some- thing, we must assume that they will remember accurately and that they have the ability to assess and report accurately on their thoughts and feelings. For example, if we ask you to tell us whether you agree or disagree with the statement “I have always liked cats,” you must remember not only how you feel about cats now but also how you felt about cats previously.
• Individuals will report honestly their thoughts and feelings. Even if people are able to report correctly about themselves, they may choose not to do so. Sometimes people respond how they think the tester wants them to respond, or they lie so that the outcome benefits them. For example, if we ask test takers whether they have ever taken a vacation, they may tell us that they have even if they really have not. Why? Because we expect most individuals to occasionally take vacations, and therefore the test takers think we would expect most individuals to answer “yes” to this question. Criminals may respond to test questions in a way that makes them appear neurotic or psychotic so that they can claim that they were insane when they committed crimes. When people report about themselves, we must assume that they will report their thoughts and feelings honestly, or we must build validity checks into the test. We discuss some the practical implications of this assumption in Chapter 15.
• The test score an individual receives is equal to his or her true score plus some error, and this error may be attributable to the test itself, the examiner, the examinee, or the environment. That is, a test taker’s score may reflect not only the attribute being measured but also things such as awkward question wording, errors in administration of the test, examinee fatigue, and the temperature of the room in which the test was taken. When evaluating an individual’s score, we must assume that it will include some error.