I think it would be a interesting exercise to judge grades the same way we judge other types of psychometric testing. Test-retest reliability / concurrent reli

I think it would be a interesting exercise to judge grades the same way we judge other types of psychometric testing. Test-retest reliability / concurrent reliability (not sure which applies): Doesn't look great. Grades can vary dramatically between classes, even if those classes are closely related. Predictive validity: Not sure. I'm not sure what, if anything, GPA is meant to predict, and I've read varying things about how well it predicts success in one's career. Face validity / construct validity: Abysmal. What are grades supposed to measure, anyway? Work ethic? Motivation? Willingness to obey authority? Intelligence? Demonstrated mastery of the material? I have no idea. Whatever they're meant to measure, they measure a lot of things no one would want them to, like the student's race and sex, whether or not they're working while in school, when the class starts, etc.