BCC model
Banker, Charnes and Cooper developed a model (BCC) with variable returns to scale (VRS).
input oriented
![bcc[1].JPG](/uploadimages/bcc[1].JPG)
Banker, R.D., Charnes, A., Cooper, W.W., 1984, "Some Models for Estimating Technical and Scale Inefficiencies in Data Envelopment Analysis," Management Science, 30(9), 1078-1092.