- Cities and Product Variety, Journal of Economic Geography, November 2015
-Winner of Urban Land Institute Prize for best paper in Journal of Economic Geography, 2015
JoEG version; working paper version; ULI presentation; 中文摘要
This paper measures restaurant variety in US cities and argues that city structure directly increases product variety by spatially aggregating demand. I discuss a model of entry thresholds in which market size is a function of both population and geographic space and evaluate implications of this model with a new data set of 127,000 restaurants across 726 cities. I find that geographic concentration of a population leads to a greater number of cuisines and the likelihood of having a specific cuisine is increasing in population and population density, with the rarest cuisines found only in the biggest, densest cities. Further, there is a strong hierarchical pattern to the distribution of variety across cities in which the specific cuisines available can be predicted by the total count. These findings parallel empirical work on Central Place Theory and provide evidence that demand aggregation has a significant impact on consumer product variety. Click here for a longer discussion.
- Spatial Competition and Cross-border Shopping (with Brian Knight), American Economic Journal: Economic Policy, November 2012
AEJ version; working paper version
This paper investigates competition between jurisdictions in the context of cross-border shopping for state lottery tickets. Our theoretical model, in which consumers consider both travel costs and lottery payoffs, predicts that per-resident sales should be more responsive to prices in small states with densely populated borders. Using weekly sales data from US lotteries and drawing identification from the rollover feature of jackpots, we estimate this responsiveness and find large effects that vary significantly across states. Using these estimates, we show that competitive pressures from neighboring states may lead to substantially lower optimal prices.
- Momentum and Social Learning in Presidential Primaries (with Brian Knight), Journal of Political Economy, December 2010
JPE version; working paper version
New York Times coverage
This paper investigates social learning in sequential voting systems. In the econometric model, candidates experience momentum effects when their performance in early states exceeds expectations. The empirical application uses daily polling data from the 2004 presidential primary. We find that Kerry benefited from surprising wins in early states and took votes away from Dean. Owing to these momentum effects, early voters had up to five times the influence of late voters in the selection of candidates, and this helps to explain the distribution of advertising expenditures. Finally, we use the estimated model to conduct two counterfactual experiments.
Working Papers and Works in Progress
- The Out-of-State Tuition Distortion (with Brian Knight, NBER WP)
- Formation and Dynamics of Ethnic Neighborhoods (with Tianran Dai and Sanghoon Lee, working title, in progress)
- Welcome! We have a New Menu: Measuring Product Responses to Competition (with Jacob Cosman, working title, in progress)