We develop a general equilibrium model of multiproduct fi…rms with quality differentiated goods. Households are characterized by an heterogeneous taste for the differentiated good and their income level. The use of non-homothetic preferences and vertical product differentiation (product...

We develop a theoretical framework to study illicit drugs markets and we estimate it using data on purchases of crack cocaine. Buyers are searching for high-quality drugs, but they determine drugs' quality (i.e., their purity) only after consuming them. Hence, sellers can rip off first-time...

We study how fragmentation of patent rights ('patent thickets') and the formation of theCourt of Appeal for the Federal Circuit (CAFC) affected the duration of patent disputes, andthus the speed of technology diffusion through licensing. We develop a model of patentlitigation which predicts...

This paper specifies and estimates a structural dynamic model of consumer demand for newand used durable goods. Its primary contribution is to provide an explicit estimationprocedure for transaction costs, which are crucial to capturing the dynamic nature ofconsumer decisions. In particular,...

This paper studies the role of intrinsic motivation, reputation and reciprocity in driving open source software innovation. We exploit the observed pattern of contributions - the 'revealed preference' of developers - to infer the underlying incentives. Using detailed information on code...

Using new data on citations to university patents and scientific publications, and measures of distance based on Google maps, we study how geography affects university knowledge diffusion. We show that knowledge flows from patents are localized in two respects: they decline sharply with distance...

The focus of the present work is to study the impact of the second-hand market the collusivebehavior. I analyze firms' preferences for having an active second-hand market and whetherpolicies (i.e. leasing policy, buy-back policy and warranty policy) that affect the functioningof the second-hand...

Theory predicts that optimal effective corporation tax rates will benegatively related to industry specific sunk costs, and hence industryconcentration. Governments should tax industries with monopolistic powersoftly. Evidence suggests that this Schumpeterian (1942) principle ofcorporate...

This paper introduces a novel analysis of the classic "persistence of leadership" question, and applies it to a newly constructed dataset for Japanese manufacturing. The analysis rests on an appeal to an empirical "scaling relationship" between current market share and the variance of changes in...

In many industries broad cross-license agreements are considered a useful method toobtain freedom to operate and to avoid patent litigation. In this paper I study thepreviously neglected dynamic trade-off between litigating and cross-licensing that firmsface to protect their intellectual...