Citation
Nicholas Stephanopoulos & Eric M. McGhee, The Measure of a Metric: The Debate Over Quantifying Partisan Gerrymandering, 70 Stan. L. Rev. 1503 (2018).
Abstract
Over the last several years, there has been an unprecedented outpouring of scholarship on partisan gerrymandering. Much of this work has sought either to introduce new measures of gerrymandering or to analyze a metric — the efficiency gap — that the authors previously developed. In this Essay, the authors reframe the debate by presenting a series of criteria that can be used to evaluate any gerrymandering metric: (1) consistency with the efficiency principle; (2) distinctness from other electoral values; (3) breadth of scope; and (4) correspondence with U.S. electoral history. They then apply these criteria to both the efficiency gap and rival measures. The efficiency gap complies with the criteria under all circumstances. Other metrics, in contrast, often violate the efficiency principle and cannot be used in certain electoral settings.