Answer: The equivalence error caused by improper equivalence processing in examination equivalence is the systematic error of equivalence, also called equivalence deviation. For example, the subjects who took the two tests were two independent groups with different abilities. If they are treated as random groups or equal groups, the equivalent results will be biased.

In testing equivalence, the equivalent standard error caused by sampling and the equivalent deviation caused by improper handling methods often exist together, and sometimes there are contradictions. For the problem of equivalence system error, anchor test can be added, and the equivalence relationship between the two forms can be found by using the same set of questions, and the two test forms can be associated as equivalence, thus correcting the equivalence deviation.