生產力驅動因子、廠商異質性及其內生非線性發展

Productivity Drivers, Firm Heterogeneity and Endogenous Nonlinearities

本文採用一傳統獨佔性競爭市場環境，在廠商具有生產力的異質特性下，建構產業進出市場的完全內生化動態機制。在模型中，廠商決定是否投資其生產力驅動因子。而於此環境下，兩個曾誤的長期均衡將會產生。其一，某些生產力較低之廠商將不再投資強化其生產力驅動因子，而他們的生產力會迅速下降至零並且退出市場。其二，其他廠商將會投資強化其生產力驅動因子，而他們的生產力、利潤及產出都呈現長期內生波動。此模型將可以描述國際貿易以及外人直接投資之可能性。

The paper takes a conventional monopolistic competition market environment, with firm heterogeneity at the productivity level, as the scenario to construct a fully endogenous dynamic mechanism of entry and exit in the industry. At each time period, firms decide whether to invest or not on the forces that determine their own productivity. The way in which the model is designed generates a twofold long-term equilibrium: some firms, with initial low levels of productivity, will never invest in productivity drivers, their productivity falls progressively to zero and they are irreversibly driven out of the market. All the other firms will find it advantageous to invest intermittently in productivity drivers; for these, productivity, profits and output will exhibit long-term endogenous fluctuations. The model is adapted, in a second stage, in order to contemplate the possibilities of international trade and foreign direct investment.