We estimate the demand for a videocalling technology in the presence of both network effects and heterogeneity. Using a unique dataset from a large multinational firm, we pose and estimate a fully dynamic model of technology adoption. We propose a novel identification strategy based on...

We analyze entry, pricing and product design in a model with differentiated products. Under plausible conditions, entry into an initially monopolized market leads to higher prices for some, possibly all, consumers. Entry can induce a misallocation of goods to consumers, segment the market in a...

We analyze alternative policies such as a disposal content fee, a subsidy for recyclable designs, unit pricing of household disposal, a deposit-refund system, and a manufacturer `take-back' requirement. In order to identify the problem being addressed, we build a simple general equilibrium model...

Product redesigns happen across virtually all types of products. While there is substantial evidence that new varieties of goods increase welfare, there is little evidence on the effect of product redesigns. We develop a model of redesign and exit decisions in a dynamic oligopoly model (a la...

What is inequality in health? Are economists' standard tools for measuring income inequality relevant or useful for measuring it? Does income protect health and does income inequality endanger it? I discuss two different concepts of health inequality and relate each of them to the literature on...

Ideas about what is "fair" above and beyond the individual's position in the income ladder influence preferences for redistribution. We study the dynamic evolution of different economies in which redistributive policies, perceptions of fairness, inequality and growth are jointly determined. We...

I suppose that consumers see a firm as fair if they cannot reject the hypothesis that the firm is somewhat benevolent towards them. Consumers that can reject this hypothesis become angry, which is costly to the firm. I show that firms that wish to avoid this anger will keep their prices rigid...

In Fairness versus Welfare, we advance the thesis that social policies should be assessed based entirely on their effects on individuals' well-being. This thesis implies that no independent weight should be accorded to notions of fairness (other than many purely distributive notions). We support...