to evaluate the efficiency of firms in converting inputs – in the form of shareholders' funds, liabilities and costs … - into sales. The efficiency scores are then modelled in a random parameter framework where one of the determinants of … current period efficiency is the firm's own lagged efficiency. In a parsimonious model, we find that the extent to which …

be distinguished from inter-institutional differences in efficiency. The approach used here therefore resembles in some … respects the non-parametric methods of efficiency evaluation. We report also on measures of average incremental cost of …