Data envelopment analysis or DEA is a linear programming technique developed in the work of Charnes, Cooper and Rhodes (1978). It is a non-parametric technique used in the estimation of production functions and has been used extensively to estimate measures of technical efficiency in a range of industries (Cooper, Seiford and Tone, 2000). Tutorial Warwick Data Envelopment Analysis (WDEA) CRS, Guide Warwick Data Envelopment Analysis (WDEA) CRS.