Consumer Search, Price Dispersion, and International Relative Price Volatility

This paper develops a model of consumer search consistent with the evidence of substantial price dispersion within countries. This model is used to study international relative price fluctuations. Consumer search frictions permit firms to price discriminate across markets based on the local wage of consumers. With price dispersion, the market price of a good does not measure its resource cost. This breaks the tight link between relative quantities and relative prices implied by most models. We show that volatile and persistent fluctuations in relative wages lead to volatile and persistent fluctuations in relative prices at the disaggregate level. These deviations from the law of one price substantially increase international relative price volatility. With productivity and taste shocks, the model generates international business cycles that closely match the data