Abstract:
The evaluation of efficiency scores in data envelopment analysis is based on
the construction of artificial decision making units subject to some assump-
tions, usually requiring convexity of the production possibility set. This
demands divisibility in input and output, which is not always possible. The
so-called free replicability model, proposed by Henry Tulkens, permits input
and output to enter in only discrete amounts. The model is of a mixed
integer programming type, for which the number of variables, here corre-
sponding to the decision making units, may be critical in order to reach an
optimal solution.
We suggest to use column generation techniques to include only those
decision making units that may contribute to the creation of an optimal
solution.