Test Validity and Reliability
by Judy Dix
1. Reliability: Does the test yield similar score rankings *consistently?
1.1. Test-ReTest
1.1.1. Correlation of test-retest scores
1.1.1.1. Reliability Coefficient
1.2. Alternative Form
1.2.1. Correlation of two distributions of two equivalent tests
1.3. Internal Consistency
1.3.1. Correlation of one item of basic content with similar items.
1.3.1.1. Split-half Methods
1.3.1.2. Kuder-Richardson Methods
2. Validity: Does the test measure what it is supposed to measure?
2.1. Content Validity Evidence
2.1.1. Verification as to whether the test measures the instructional objectives.
2.2. Criterion-Related Validity Evidence
2.2.1. Concurrent
2.2.1.1. Measures administered simultaneously with measure to be validated.
2.2.1.1.1. Validity Coefficient
2.2.2. Predictive
2.2.2.1. Measures the ability of the test to predict future behavior or performance
2.2.2.1.1. Predictive Validity Coefficient
2.3. Construct Validity Evidence
2.3.1. Measures the relationship of information as it corresponds with a specified theory