Trade between symmetric countries, heterogeneous firms, and the skill premium

This paper examines the effects of trade liberalization between symmetric countries on the skill premium. I introduce skilled and unskilled labour in a model of trade with heterogeneous firms à la Melitz (2003) and assume a production technology such that more productive firms are more skill intensive. I show that the effects of trade liberalization on wage inequality crucially depend on the type of trade costs considered and on their initial size. While fixed costs of trade have a potentially non-monotonic effect on the skill premium, a drop in variable trade costs unambiguously and substantially raises wage inequality.