@techreport{Brummer1999Problems,
abstract = {This paper explores the consequences for parametric and non-parametric efficiency levels
and rankings when using grouped instead of individual Decision Making Units (DMU). The
bias results due to the differences of the grouped DMUs frontier compared to the individual
DMUs frontier. Monte Carlo experimentation is used to evaluate the empirical dimension on
the estimated efficiency levels and rankings. These results are illustrated with an empirical
example using a sample of German farms. The bias in ranking is found to be substantial.
Finally, a correction procedure is developed to improve the results when only grouped data are
available.},
author = {Bernhard Br\"{u}mmer and Holger D. Thiele},
copyright = {http://www.econstor.eu/dspace/Nutzungsbedingungen},
keywords = {330; Grouped data; aggregation; DEA; SFA; Data-Envelopment-Analyse; Technische Effizienz; Agrarstatistik; Aggregation; Bias; Theorie; Deutschland},
language = {eng},
number = {9906},
title = {Problems of using grouped DMUs for efficiency measurement: Monte Carlo experiments, empirical dimension, and a correction procedure},
type = {FE Workingpaper / Universit\"{a}t Kiel, Department of Food Economics and Consumption Studies},
url = {http://hdl.handle.net/10419/23576},
year = {1999}
}
