One of Us Cannot Be Wrong: The paradox of achievement gaps

Abstract

There are two general groups of methods of calculating achievement gaps (between groups of students in education) in common current usage, similar to those used to calculate social segregation in space and social mobility over time. Each type of method clearly seems valid to its proponents, yet their results in practice are radically different, and often contradictory. This brief paper considers both of these methods and some related problems in the calculation of achievement gaps, in an attempt to resolve the contradiction. The issue is a relatively simple one, but one with significant implications for social researchers as well as commentators in many areas of public policy using similar indicators of performance.