Why trade liberalizations increase the skill premium? To explain this empirical evidence that is in contrast with the conventional theory of Heckscher-Ohlin, I build up a general equilibrium micro-founded heterogeneous-firm model of international trade where firms make decisions on their division of labor, and firms’ skill-intensities are endogenously determined. I show why the exporters are generally more productive and skill intensive and how trade cost reductions induce more productive firms to choose a higher degree of labor specialization, become more skill intensive and start to export. I further demonstrate how such internal horizontal organizational changes, after a trade cost reduction, can directly increase aggregate skill intensity and the relative demand for skilled workers, resulting in higher skill premium in a general equilibrium setting. Lastly, I calibrate this model to the Mexican data to quantify the rise in the skill premium in the period of its trade liberalization 1985~1993.

为什么贸易自由化会增加技能溢价？为了解释这一与 Heckscher-Ohlin 的传统理论相反的经验证据，我建立了一个一般均衡微观建立的国际贸易异质企业模型，其中企业就其劳动分工和企业的技能强度做出决策是内生决定的。我展示了为什么出口商通常更具生产力和技能密集型，以及贸易成本的降低如何促使生产力更高的公司选择更高程度的劳动力专业化，变得更加技能密集并开始出口。我进一步展示了这种内部横向组织变化如何在贸易成本降低后直接增加总体技能强度和对熟练工人的相对需求，在一般均衡环境中导致更高的技能溢价。最后，我将这个模型与墨西哥的数据进行校准，以量化 1985~1993 年贸易自由化时期技能溢价的上升。