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Berry, S., James A. Levinsohn, and A. Pakes. 2004. "Differentiated Products Demand Systems From a Combination of Micro and Macro Data: the New Car Market." Journal of Political Economy, 112(1): 68-105.
In this paper, we consider how rich sources of information on consumer choice can help to identify demand parameters in a widely used class of differentiated products demand models. Most important, we show how to use "second-choice" data on automotive purchases to obtain good estimates of substitution patterns in the automobile industry. We use our estimates to make out-of-sample predictions about important recent changes in industry structure.