Validity

• Validity is a judgement or estimate of how well a test measure what it is supposed to measure.
• Norms are a way of deriving meaning. It is the test performance of a specific group that become a point of reference.
• Validation is the process of gathering and evaluating evidence of validity.
• Internal Validity refers to the degree of control among variables in the study, which may be increased through random assignment.
• External Validity refers to the generalizability of research results, which may be increased through random selection.
• Developed by Charles Spearman, Factor Analysis is a method designed to identify factors or specific variables that are attributes, characteristics, or dimensions in which people may differ.
• THEORETICAL FRAMEWORKS OF PSYCHOMETRY

  • Classical Test Theory
  • Domain Sampling Theory
  • Item Response Theory
• Classical Test Theory states that a score on an ability test is presumed to not only reflect the test taker's ability being measured, but also the error.
• Domain Sampling Theory states that test scores have specific sources of variation that contribute to the overall score.
• Item Response Theory focuses on item difficulty, and presumes the probability of a person with X ability will be able to perform at level Y in a test.
• VALIDITY IN PSYCHOMETRIC TESTS

  • Face Validity
  • Content Validity
  • Construct Validity
  • Criterion Validity
• Age differentiation assesses if the construct changes with age.
• Convergent validity refers to how closely a test is related with other tests that measure the same or similar constructs.
• Discriminant validity refers to how well a test correlates to unrelated constructs.
• Contrasted Group Validity examines the variation across multiple comparison groups by using the test on a group that does not have the construct the test is designed to measure.
• In the context of validity, Factor Analysis counts the number of dimensions a construct has. It is valid if the review of literature matches with the factors.
• Concurrent validity shows the relationship between test scores and an external criterion being measured at the same time.
• Predictive validity is the degree to which test scores accurately predict an external criterion that will be measured somewhat later.
• Content validity refers to the appropriateness of test items, which must fits the conceptual definition established by test authors and experts.
• Face validity refers to the presentability or physical appearance of the test, rather than the validity of the construct itself.
• Criterion is the numerical expression or observable indicators of a test construct.
• Criterion validity is the expression of correlation between scores on the test and external criteria in which the test is theoretically related.