People who study tests, whether they are good tests are not, use the concept of “reliability.” A reliable test is one that measures the knowledge of material consistently across time, individuals, and situations. So for example, if you give a history test on Monday and 20 percent get A’s and 20 percent get F’s, and then you re-test the next Monday and a different 20 percent get A’s and F’s, the test is not reliable. In the immigration context, people…