A Two-factor Model of Intra-industry Trade: A Demonstration of Robustness of Krugman’s (1980) Model

Using Cobb-Douglas production function with increasing returns to scale, this paper presents an intra-industry trade model which contains two factors, capital and labor. Thus, this paper extends Krugman’s (1980) single-factor model to a two-factor model with the entry cost. Firstly, an equilibrium analysis of closed economy is carried out. After the condition of existence and uniqueness of equilibrium is obtained, the analytic solutions are given. Secondly, it provides an analysis on trade effects. The results show that, under setup of symmetry among firms, the intra-industry trade can only enable consumers to benefit from product diversification without making firms achieve economies of scale. Obviously, this conclusion is consistent with Krugman (1980), which thus indicates robustness of Krugman’s (1980) model.