Essays on firm efficiency with imperfectly competitive input markets: an empirical analysis

In the thesis I exploit an empirical analysis on firm'?s productivity. I relate the efficiency at plant level with the input market features and I suggest an estimation technique for production function that takes into account firm'?s liquidity constraints. The main results are three. When I consider services as inputs for manufacturing firm?'s production process, I find that more competition in service sector affects positively plant?s productivity and export decision. Secondly liquidity constraints are important for the calculation of firm'?s productivity because they are a second source of firm's heterogeneity. Third liquidity constraints are important for firm'?s internationalization