The reliability of the test, also known as the reliability of the test, refers to the consistency of the results of a test after many measurements and the accuracy of the results of a measurement. The validity of a test refers to the degree to which a test can measure the properties or characteristics it wants to measure. The discrimination degree of the test refers to the degree to which the test can distinguish candidates of different levels, that is, it has the ability to distinguish candidates of different levels.

The connection and difference between reliability and validity;

1, the reliability is low and the validity cannot be high. Because if the measured data is inaccurate, the research object cannot be effectively explained.

2. High reliability, but not necessarily high validity. For example, if we accurately measure a person's economic income, it may not necessarily explain his consumption level.

3. The validity is low and the reliability may be high. For example, a study failed to explain the reasons for social mobility, but it is likely to accurately and reliably investigate various types of people in different periods.

4, high validity and high reliability.