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...

Purpose: The purpose of this paper is to improve the accuracy of evaluation efficiency by constructing parallel structures considering the main components of industrial pollutants, and then to consider some external influence factors to eliminate random errors. Design/methodology/approach: In...