f numbers described above. I could give you a pop quiz that would ask you several questions about these concepts and count how many you got right. This test might or might not be a good measurement of the construct of your actual knowledge – for example, if I were to write the test in a confusing way or use language that you don’t understand, then the test might suggest you don’t understand the concepts when really you do. On the other hand, if I give a multiple choice test with very obvious wrong ans