In this paper, we show that classical survival analysis involving censored data can naturally be cast as a ranking problem. The concordance index (CI), which quantifies the quality of rankings, is the standard performance measure for model assessment in survival analysis. In contrast, the standard approach to learning the popular proportional hazard (PH) model is based on Cox’s partial likeliho...

A new rank correlation index, which can be used to measure the extent of concordance or discordance between two rankings, is proposed. This index is based on Gini’s mean difference computed on the totals ranks corresponding to each unit and it turns out to be a special case of a more general measure of the agreement of m rankings. The proposed index can be used in a test for the independence of...

This appendix reviews and extends Cournot’s classic results, connecting them to the design of mechanisms for multilateral trade. Little in this section is “new”, as it largely seeks to unify the proofs of disparate results in the literature. However, we believe that this simple united treatment helps emphasize the connections among a variety of issues previously discussed in isolation and there...