Validity and Reliability

1. Criterion-related validity evidence: scores from a test are correlated with an external criterion (yields a numeric value). Two types: concurrent and predictive. Concurrent: deals with measures that can be administered at the same time as the measure to be validated (ex.IQ Tests) Predictive: refers to how well the test predicts some future behavior of examinees

2. Construct validity evidence: if its relationship to other information corresponds well with some theory

3. Content validity evidence: established by inspecting test questions to see whether they correspond to what the user decides should be covered by the test.

4. Reliability Definition:Does the test yield the same or similar score rankings all other factors being equal consistently?

5. Validity Definition: Does the test measure what it is supposed to measure?

6. Definitions of Validity and Reliability

7. Types of Validity

8. Internal Consistency: designed to measure a single, basic concept. Two types: split halves and odd-even reliability Split halves: splitting the test into two equivalent halves and determining the correlation between them. Odd-Even Reliability: divide test items by placing all odd-numbered items into one half and all even numbered items into the other half.

9. Alternative Forms or Equivalence: if two equivalent forms of a test, these forms can be used to obtain an estimate of the reliability of the scores from the test. Both forms are administered to a group of students, and correlate between the two sets of scores is determined. (eliminates problems of memory)

10. Test/ReTest or Stability: method of estimating reliability where the test is given twice and the correlation between the first set of scores and the second set of scores is determined. (issue - usually memory the 2nd time the test is taken)

11. There are three types of validity: Content, criterion-related and construct.

12. There are three types of reliability: test/retest or stability, alternative forms of equivalence, and internal consistency

13. Types of validity and reliability

14. Types of Reliability

15. Validity and Reliability