Trade, quality upgrading, and wage inequality in the Mexican manufacturing sector. The Quarterly

This paper proposes a new model of the link between expanding trade and rising wage inequality in developing countries, and investigates its causal implications in a newly constructed panel of Mexican manufacturing establishments. In a theoretical setting with heterogeneous rms and quality dierentiation, only the most productive rms in a developing country like Mexico enter the export market, and they produce a better-quality good for export than for the domestic market in order to appeal to richer developed-country consumers. Producing high-quality goods requires paying high wages both to white-collar and to blue-collar { but especially to white-collar { employees. An increase in the incentive for developing-country producers to export generates dierential quality upgrading within industries, as more-productive rms increase exports and produce a greater share of high-quality goods, while less-productive rms remain focused on the domestic market. This process raises wage inequality both between rms and within the rms that upgrade. The empirical part of the paper uses a major exchange rate shock { the Mexican peso crisis of late 1994 { to test this causal mechanism. I nd robust evidence that during the years of the crisis initially more-productive plants increased both white-collar and blue-collar wages and increased the relative wage of white-collar workers as compared to initially less-productive plants. This pattern is absent in the periods before or after the crisis years. The results thus provide strong support for the hypothesis that dierential quality upgrading induced by the exchange rate shock contributed to the increase in wage inequality in Mexico in the mid-1990s