Validity

Validity or Valid may refer to:

Mathematics

 * Validity (logic), a property of a logical argument

Statistics

 * Validity (statistics), the degree to which a statistical tool measures that which it is purported to measure
 * Statistical conclusion validity, establishes the existence and strength of the co-variation between the cause and effect variables
 * Test validity, validity in educational and psychological testing
 * Face validity, the property of a test intended to measure something
 * Construct validity, refers to whether a scale measures or correlates with the theorized psychological construct it measures
 * Content validity, the extent to which a measure represents all facets of a given construct
 * Concurrent validity, the extent to which a test correlates with another measure
 * Predictive validity, the extent to which a score on a scale or test predicts scores on some other measure
 * Discriminant validity, the degree to which results a test of one concept can be expected to differ from tests of other concepts that should not be correlated with this one
 * Criterion validity, the extent to which a measure is related to an outcome
 * Convergent validity, the degree to which multiple measures of the same construct lead to the same conclusion

Science

 * Internal validity, the validity of causal inferences within scientific studies, usually based on experiments
 * External validity, the validity of generalized causal inferences in scientific studies, usually based on experiments
 * Valid name (zoology), in animal taxonomy
 * Validly published name, in plant taxonomy

Other uses

 * Valid (number format), a universal number format (unum type III)
 * Valid (engraving company), a Brazilian company
 * VALID (Video Audio Line-up & IDentification), part of the GLITS broadcast television protocol
 * Validity and liceity (Catholic Church), concepts in the Catholic Church.