Search results
Results From The WOW.Com Content Network
E.g. a scale that is 5 pounds off is reliable but not valid. A test cannot be valid unless it is reliable. Validity is also dependent on the measurement measuring what it was designed to measure, and not something else instead. [6] Validity (similar to reliability) is a relative concept; validity is not an all-or-nothing idea.
Test validity is the extent to which a test (such as a chemical, physical, or scholastic test) accurately measures what it is supposed to measure.In the fields of psychological testing and educational testing, "validity refers to the degree to which evidence and theory support the interpretations of test scores entailed by proposed uses of tests". [1]
Reliability does not imply validity. That is, a reliable measure that is measuring something consistently is not necessarily measuring what you want to be measured. For example, while there are many reliable tests of specific abilities, not all of them would be valid for predicting, say, job performance.
A good assessment has both validity and reliability, plus the other quality attributes noted above for a specific context and purpose. In practice, an assessment is rarely totally valid or totally reliable. A ruler which is marked wrongly will always give the same (wrong) measurements. It is very reliable, but not very valid.
Assessment of a skill should comply with the four principles of validity, reliability, fairness and flexibility. Formative assessment provides feedback for remedial work and coaching, while summative assessment checks whether the competence has been achieved at the end of training.
Assessment tools that rely on ratings must exhibit good inter-rater reliability, otherwise they are not valid tests. There are a number of statistics that can be used to determine inter-rater reliability. Different statistics are appropriate for different types of measurement.
Reliability cannot be estimated directly since that would require one to know the true scores, which according to classical test theory is impossible. However, estimates of reliability can be acquired by diverse means. One way of estimating reliability is by constructing a so-called parallel test. The fundamental property of a parallel test is ...
[3] Criterion validity is typically assessed by comparison with a gold standard test. [ 4 ] An example of concurrent validity is a comparison of the scores of the CLEP College Algebra exam with course grades in college algebra to determine the degree to which scores on the CLEP are related to performance in a college algebra class. [ 5 ]