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Validity is the extent to which a tests measure what is supposed to measure. Reliability is the extent to which a test is repeatable and yeilds consistent results.
Both reliability and validity are important in any psychology testing. For a test to be acceptable in psychology it mus have both reliability and validity. It i therefore, important for a test to have both high reliability and high validity. This is because both tests are equally important if the test is to be successful.
If a test has reliability but not validity then it might end up measuring the wrong thing and give wrong results. Similarly if a test lacks reliability, then the results can only be inconclusive since test will give different results from the same subject.
It is therefore important for a test in psychology to have both high validity and reliability.
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