Rank Disequilibrium in Multiple-Criteria Evaluation Schemes

Jon Hodge, Grand Valley State University

According to Pruitt and Kim, rank disequilibrium “exists when there are multiple criteria for assessing people’s merit or contributions, and some people are higher on one criterion and lower on another criterion than others.”  Rank disequilibrium can be a source of social conflict when evaluees perceive inequities in the way ratings on individual criteria are combined to yield overall evaluations.  In this talk, we will investigate a mathematical model of multiple-criteria evaluation, developing the notion of a rank aggregation function and exploring several desirable properties of such functions.  We will discover that, as in many other social choice problems, finding a perfect rank aggregation function is a difficult—and perhaps even impossible—task.