Recyclable outputs in production process: a data envelopment analysis approach

Abstract

In conventional data envelopment analysis (DEA) models, it has been assumed that the produced outputs go on the outside of the system and they are considered as final outputs. However, in real applications there are systems in which some portion of the produced outputs are possibly used as inputs in the systems. These outputs are referred to as recyclable outputs and they enter the system once again and are consumed as inputs. In other word, the main system is fed by a mixture of external inputs and some portion of the produced outputs. The present paper is concerned with production systems with recyclable outputs. We will propose a modification on the standard DEA model to incorporate such outputs. Numerical example is used to demonstrate the approach.