Some Remarks on Modified FDH

One of the tools in theoretical and empirical work on the measurement of productive efficiency is the socalled Free Disposal Hull (FDH) method. As a result of its very generous character, many of the observations belonging to an evaluated dataset are labeled efficient by this method. Modified FDH, similar in spirit as Andersen and Petersen's modified Data Envelopment Analysis, may thus be used to discriminate between FDH-efficient units. We aim to show why particularly for FDH this method seems quite apt and may be called for as a valuable complementary tool to standard FDH analysis. Copyright Kluwer Academic Publishers 1998