We analyze a model of cost-reducing R&D and compatibility decisions by two platforms. After an exogenous improvement in the efficiency of R&D, each platform has a heightened incentive to make its software incompatible with the rival's hardware device to avoid being dominated in the hardware...

In this paper, I examine the welfare consequences of conventional approximation methods in business cycle analysis: the log-linear approximation of model dynamics and the second-order approximation of social welfare. In a canonical New Keynesian model, the approximation around the deterministic...

We analyze a dynamic multi-pollutant problem where abatement costs of several pollutants are not separable. The pollutants can be either technological substitutes or complements. Environmental damage is induced by the stock of accumulated pollution. We find that optimal emission paths are...

We analyze a dynamic multi-pollutant problem where abatement costs of several pollutants are not separable. The pollutants can be either technological substitutes or complements. Environmental damage is induced by the stock of accumulated pollution. We find that optimal emission paths are...

We analyze a dynamic multi-pollutant problem where abatement costs of several pollutants are not separable. The pollutants can be either technological substitutes or complements. Environmental damage is induced by the stock of accumulated pollution. We find that optimal emission paths are...

Large e-commerce retailers and department stores function as marketplaces for millions of sellers, and consumers rely on the platform's assortment and display decisions to examine different sellers and make purchase decisions. Traditionally, the primary objective of these marketplaces for...

Previous research on optimal R&D subsidies has focussed on the long run. This paper characterizes the optimal time path of R&D subsidization in a semi-endogenous growth model, by exploiting a recently developed numerical method. Starting from the steady state under current R&D subsidization in...