1. Characteristics of Psychology Tests
Objectives:
Identify 3 ways of measuring reliability.
Explain test standardization
Explain how test validity is assessed
Vocabulary:
Reliability
Validity
Percentile system
Norms

2. Characteristics of Psychological Test
They all try to make it possible to find out a great deal about a person in a short period of time.
They try to make predictions about:
Career interest
Individual desires, interests, and attitudes
Reveal psychological problems
They can show how an individual compares to others.
They can help people understand things about themselves more clearly

3. Limitations of Psychological Tests
We tend to forget that test are merely tools for measuring and predicting human behavior.
Test results are not an end in unto itself.
Using test to make decisions about something needs to be the more fair and accurate measure than other criteria
Fairness and usefulness depends on:
Reliability
Validity
Standardization

4. Test Reliability Definition: Refers to a test’s consistency
Does the test have the ability to yield the same result under a variety of similar circumstances?
Test-retest reliability
Interscorer reliability
Scorer reliability
Split-half reliability

5. Test-Retest Reliability
If the person retakes the test or takes a similar test within a short period of time, do they receive approximately the same score?

6. Interscorer Reliability
Does the test yield the same results when scored at different times by different people?

7. Scorer Reliability
If the same teacher grades papers at different times, does he or she score the same paper differently?

8. Split-Half Reliability
Randomly divide the test in half and score each separately.
The two scores should be approximately the same.
It should not have sections on which the person scores high and others on which he or she scores low.

9. Test Validity
Definition: The ability of a test to measure what it is intended to measure.
Does the test measure what it is supposed to?
What is the purpose of the test?
One of the chief methods is to find out how well a test predicts performance.
Predictive Validity

10. Standardization Criteria:
Standardized test must be administered and scored the same way every time.
Established norms are used that have been based on the scores of a large group of people.

11. Establishing Norms
Transfers a raw score into a percentile system, which resembles a bell curve.
Place the scores in order from the highest to the lowest.
Percentiles are assigned according to the percentage of scores that fall above or below the mean.
The percentiles established from the test by the large test group are called the norm.
Norms only refer to what has found to be the average for a particular group.

12. Things to Remember
Do you think that if you took the same test again, you would receive a similar score?
Does your performance on the test reflect your usual performance in the subject?
If you were to compare your score with those of your classmates, would it reflect your general standing within the group?