validity

ValidityBy

Jean DJ. Naval

Why evaluate tests?• To make sure that a test measures the skill,

trait, or attribute it is supposed to measure• To yield reasonable consistent results for the

same individual• To measure with reasonable degree of

accuracy

A good test must first of all be valid.

Validity• Refers to the extent to which a test

measures what it purports to measure.• Does the measure what it is suppose

to measure?

TYPES OF EVIDENCE

• CONTENT-RELATED VALIDITY- the adequacy and representativeness of

learning outcomes to be measured.- is assessed by systematically comparing a

test item with instructional objectives to see if they match. Content validity evidence does not yield a numerical estimate of validity evidence.

TYPES OF EVIDENCE

• CRITERION-RELATED VALIDITY– Is established by correlating test scores with

an external standard or criterion to obtain a numerical estimate of validity evidence.

TYPES OF CRITERION-RELATED VALIDITY EVIDENCE

1. Predictive Validity- involves the use of criterion and a predictor.

- determined by correlating test scores with a criterion measure collected after a period of time passed.2. Concurrent Validity- use the general average of the students.

- determined by correlating test scores with a criterion measure collected at the same time.

TYPES OF EVIDENCE• CONSTRUCT-RELATED VALIDITY

- Refers to how well a performance on a particular set of tasks or components can be explained in terms of some psychological construct or trait.

-determined by finding whether the test results corresponds with scores on other variables as predicted by some rationale or theory.

TYPES OF EVIDENCE• CONSTRUCT-RELATED VALIDITY

- Refers to how well a performance on a particular set of tasks or components can be explained in terms of some psychological construct or trait.• DISCRIMANT VALIDITY

- shows a certain psychological test correlated little or not at all with the construct under consideration.

• The adequacy of validity evidence depends on both the strength of the validity coefficient and the purpose the test is being used for.

• Group variability affects the strength of the validity coefficient.

• Validity Coefficient should be considered in terms of the relevance and the reliability of the criterion or standard.– A correlation coefficient

Principles In Interpreting Validity