The temporal behavior of scale economies within A banking firm

Examining the time path of the scale economies has not received much attention until recently. Moreover, the time path of scale economies for a given firm has not been studied in the banking literature at all. Examining scale economies, either from cross-sectional or panel data, based only on a single estimate ignores the dynamic behavior (both cost- and production-wise) of a banking firm as well as of the banking industry. We study the time-varying scale economies of commercial banking firms. We employ the Kalman-filter approach in estimating the translog cost function. The Kalman filter allows the parameters of the translog cost function and therefore the scale economies to be time dependent and varying. The estimation results indicate significant variation in inter- and within-firm scale economies over time for sample banks.