Supervised dimension reduction methods have been extensively applied in different scientific fields like biology and medicine in recent years. However, they have hardly ever been used in micro economics, and in particular cost function modeling. Nonetheless, these methods can also be useful in...

Quality of service is of major economic significance in natural monopoly infrastructure industries and is increasingly addressed in regulatory schemes. However, this important aspect is generally not reflected in efficiency analysis of these industries. In this paper we present an efficiency...

Since the 1990s, efficiency and benchmarking analysis has increasingly been used in network utilities research and regulation. A recurrent concern is the effect of environmental factors that are beyond the influence of firms (observable heterogeneity) and factors that are not identifiable...