Increasing dispersion of skills and rising earnings inequality

摘要

In recent decades many countries have simultaneously liberalized their trading regimes and expanded their education systems. The theoretical effect of these regime shifts on the wage differential between skilled and unskilled workers is ambiguous. On the one hand, openness to trade causes demand shifts in the labor market which may widen or narrow the differential. This result depends on whether the unskilled wage is depressed, as in the case of importing countries, or raised, as in the case of exporting countries. On the other hand, an increased supply of more educated workers reduces their wages and narrows the skill wage gap. In this study of the labor market of Hong Kong, we document that recent changes in response to the trade liberalization of Mainland China and expanded access to education have increased the earnings differential between skilled and unskilled workers. Using detailed census data, we argue that the main reason for this outcome is the widened dispersion of skills across the earnings distribution, resulting from demand and supply shifts in the labor market caused by trade openness and expanded access to higher education.