Measuring the relative balance of DMUs

In basic Data Envelopment Analysis (DEA) models, the weights of performance criteria are endogenously determined, assigning to each decision‐making unit (DMU) its best possible efficiency score. This property is widely considered to be a major strength of the method, but it is also a source of considerable problems concerning performance assessment and performance control. Such problems result from the possibility of zero‐value weights that exclude criteria from the evaluation. Unlike approaches that deal with this issue by incorporating value judgments into the analysis, we suggest a complementary balance score that is derived from the given data set. This score evaluates the extent to which a DMU avoids concentration on only some of the crucial performance criteria. One of the possible decisions resulting from a balance analysis is to reduce the set of DMUs considered to serve as benchmarks. For this case, a modified CCR–O model is presented.