AREAS where the LEARNER commits mistakes. Administering a test is just one of the ways of doing that.A Test: It is a procedure intended to establish the quality, performance, or reliability of something. Test reliability and validity are two technical properties of a test that indicate the quality and usefulness of the test.Characteristics of a Good Test:Validity:The test is considered valid if it measures what it has been designed to measure. For example, a test designed to measure personality must measure the ‘personality’ and not some other traits.Also, if a test is valid, it is definitely reliable. i.e. if a test produces accurate results, they should be consistent. E.g., if a test designed to measure mental ability and it does measure that, then, is bound to give consistent scores.Reliability:It means the consistency with which a test yields the same result over time in MEASURING whatever they do measure.For example, a test designed to test the IQ of students should produce the same result even when it is administered again after a short while.Also, a test can be reliable without being valid i.e. the results might be consistent, but they’re not necessarily correct.E.g., if a thermometer is malfunctioning, it will still provide a consistent result on checking the temperature.Objectivity: A test is objective when it makes for the elimination of the scorer’s personal opinion or biased judgment.Usability: The test must have a practical value from time, economy, and administration points of VIEW. It also refers to how satisfied learners are with that evaluation process.A test can be reliable without being valid.However, a test cannot be valid unless it is reliable.Hence, it can be concluded from the given points that if a test is valid, it is also reliable.