An alternative approach in the estimation of returns to scale under weight restrictions

This paper discusses the issue of returns to scale (RTS) under weight restrictions in data envelopment analysis (DEA). We first review Tone's method [K. Tone, On returns to scale under weight restrictions in data envelopment analysis, Journal of Productivity Analysis 16 (2001) 31-47] for estimating returns to scale under weight restrictions. Then a new approach is introduced for this task, based upon the sum of the optimal lambda values in the weighted CCR model. The equivalence of this method and Tone's method is proved. We then apply the method to a real world data set.