When analyzing productivity and efficiency of firms, stochastic frontier models are very attractive because they allow, as in typical regression models, to introduce some noise in the Data Generating Process. Most of the approaches so far have been using very restrictive fully parametric...

A primal index of productivity change is introduced which decomposes exactly in three components: technical change, technical efficiency change and average scale economies (radial scale change). The proposed index is invariant to movement along indifference surfaces and it collapses to the...

The recent nancial crisis highlighted how banks' funding and investment portfolios are associated with their risk taking. In a "normal" DEA banking efficiency model this risk element, embedded in banks' business models, is indicated by possibly inappropriate mixes of funding portfolio and/or...