CCR model
In the DEA methodology, formerly developed by Charnes, Cooper and Rhodes (1978) (CCR), efficiency is defined as a weighted sum of outputs to a weighted sum of inputs, where the weights structure is calculated by means of mathematical programming and constant returns to scale (CRS) are assumed.
input oriented
![ccr[1].JPG](/uploadimages/ccr[1].JPG)
Charnes, A., Cooper, W.W., and Rhodes, E., 1978, "Measuring The Efficiency of Decision Making Units," European Journal of Operational Research, 2, 429-444.