We study a dynamic duopoly model with differentiated products and network externalities. New consumers appear each period and the value of the product depends on the size of the network in the current and in the previous period, for example due to availability of add-ons or quot;softwarequot;....

Since 1914, the U.S. Senate has been elected and incumbent senators allowed to run for reelection without limit. This differs from several other elected offices in the U.S., which impose term limits on incumbents. Term limits may harm the electorate if tenure is beneficial or if they force high...

Since 1914, incumbent U.S. senators running for reelection have won almost 80% of the time. We investigate why incumbents win so often. We allow for three potential explanations for the incumbency advantage: selection, tenure, and challenger quality, which are separately identified using...

Why are distortionary policies used when seemingly Pareto improvements exist? According to a standard textbook argument, a Pareto improvement can be obtained by eliminating the distortions, compensating the losers with a lump sum transfer, and redistributing the gains that are left over. We...

Why are trade barriers often used to protect home producers, even at the cost of introducing deadweight losses from higher commodity prices? We add an informational friction to the standard textbook argument in favor of free trade, and show that trade restrictions may be a more effcient policy...

We estimate a structural model of the market for automatic teller machines (ATMs) in order to evaluate the implications of regulating ATM surcharges on ATM entry and consumer and producer surplus. We estimate the model using data on firm and consumer locations, and identify the parameters of the...

We seek to analyze the extent and sources of network externalities for the automated clearinghouse (ACH) electronic payments system using a quarterly panel data set on individual bank adoption and usage of ACH. We provide three methods to identify network externalities using this panel data. The...