Abstract
Undesirable outputs are increasingly considered in data envelopment analysis (DEA) for environmental performance assessment
because of hot environment issues. However, many practical conditions are not considered during modeling undesirable output
together with desirable outputs and inputs. In this paper, we presented several new approaches with considering weight
constraints between undesirable outputs and inputs. Then we constructed cross-efficiency models for measuring eco-efficiency.
Finally, we applied the developed models to evaluate the performance of 25 OECD nations in the time interval 2007-2009 so as
to illustrate the usefulness of the new presented models. Some interesting finds are described as resulting from this application.