Econometric models wishing to estimate relevant parameters for agricultural policy analysis are increasingly relying on unbalanced panels of farm-level data. Since in the agricultural economics literature such models have often been estimated through simplified approaches, in this paper we try to verify whether the adoption of more sophisticated panel data techniques may impact the estimation results. For this reason, the policy model by Moro and Sckokai (1999) has been re-estimated using techniques recently developed in the econometric literature. The preliminary results show a strong impact on the estimations. This seems to suggest that the adoption of proper panel-data techniques is likely to be very important in order to obtain reliable estimates of some key policy parameters.