Title: Malthusian Migrations (with Romain Wacziarg)

We argue that societies with higher fertility experience increased levels of emigration. During the Age of Mass Migration, persistently high fertility created a large reservoir of surplus labor that could find better opportunities in the New World. We denote such migrations, from labor-abundant to land-abundant regions, as Malthusian migrations. Our results hold in a variety of datasets and specifications, across countries, regions, individuals, and periods. Using linguistic distance from French and twin births as instruments for fertility in crowdsourced genealogical data, we estimate a large effect of fertility on out-migration. Within households, later born children were more likely to migrate as fertility increased, particularly in regions with egalitarian inheritance. We develop a Malthusian model allowing for emigration as a way to escape population pressures, alleviating the negative effects of high fertility and contributing to the emergence of modern economic growth.

Title: Nonparametric Estimation of Demand with Switching Costs: the case of Habitual Brand Loyalty

Abstract

We study habitual brand loyalty, one of the earliest empirically-studied forms of switching costs and a classic source of structural state-dependence in consumer demand. Auxiliary instruments and economically-motivated restrictions can tighten nonparametric bounds on the extent of brand loyalty in choice panel data. We also prove that the canonical dynamic discrete-choice model, nested in our nonparametric framework, has “built-in” exclusion restrictions that semiparametrically identify the discount factor, in general, and point identify it for standard parameterizations of switching costs. Case studies of several large consumer goods categories show that brand loyalty accounts for at least 10.8% but no more than 72.2%of the observed choices across categories studied. In some categories, it accounts for over 90% of observed repeat-purchase behavior. Consumers are found to be forward-looking, but more impatient than would be implied by the real rate of interest.

Keywords: habitual brand loyalty, dynamic potential outcomes, dynamic discrete choice, discount factor, partial identification, state dependence