The micro-macro disconnect of purchasing power parity

"The persistence of aggregate real exchange rates is a prominent puzzle, especially since international relative prices in microeconomic data adjust much faster. This paper finds that adjustment to the law of one price in disaggregated data is not just a faster version of the adjustment to purchasing power parity in the aggregate data; while aggregate real exchange rate adjustment works through the foreign exchange market, microeconomic adjustment works through the goods market. These distinct adjustment dynamics appear to arise from distinct classes of shocks generating micro and macro price deviations. A vector error correction model nesting aggregate and disaggregated relative prices permits identification of distinct macroeconomic and good-specific shocks. When half-lives are estimated conditional on shocks, the macro-micro disconnect puzzle disappears: microeconomic relative prices adjust to macro shocks just as slowly as do aggregate real exchange rates. These results provide evidence against theories of real exchange rate behavior based on sticky prices and on heterogeneity across goods"--National Bureau of Economic Research web site.