The Malmquist productivity index studies productivity change, that is, the technical progress or regress together with the efficiency changes over time. In a nonparametric framework, the index can be estimated by data envelopment analysis (DEA). In this paper, first all inputs are divided into...

A number of studies have used data envelopment analysis (DEA) to evaluate the performance of the countries in Olympic Games. While the fact that numbers of three kinds of medal must only take integer values is ignored. This study discusses, by means of integer-valued DEA model, the performance...