Estimation and decomposition of productivity change when production is not efficient: a paneldata approach

This paper addresses estimation and decomposition of productivity change, which is mostly identified as technical change under constant (unitary) returns to scale (CRS). If the CRS assumption is not made, productivity change is decomposed into technical change and scale effects.Furthermore, if inefficiency exists, it also contributes to productivity change. Here we decompose productivity change into efficiency change, technical change, and scale effects. Three alternative approaches using parametric production, cost, and profit functions, which differ in terms of behavioral assumptions on the producers and data requirements, are considered.