We consider competition among n sellers when each of them sells a portfolio of distinct products to a buyer having limited slots (or shelf space). We study how bundling affects competition for slots. When the buyer has k number of slots, efficiency requires the slots to be allocated to the best...

We study the problem of defining the product-variety portfolio of a firm in a competitive environment. Large portfolios have become prevalent in many industries supported by competitive pressures and the expectations of increasing revenues due to a wider offer. Such practice, however, is often...

This paper provides a new benchmark for the analysis of the international diversification puzzle in a tractable new open economy macroeconomic model. Building on Cole and Obstfeld (1991) and Heathcote and Perri (2009), this model specifies an equilibrium model of perfect risk sharing in...