Paul Samuelson is renowned as a debunker of Alfred Marshall. This chapter reviews his assessments of Marshall. It concludes that, although the conventional view is correct, it is important also to recognise that Samuelson considered Marshall to have been a great economist, albeit one who could...

We characterize the equilibrium and optimal resource allocations in a general equilibrium model of monopolistic competition with multiple asymmetric sectors and heterogeneous firms. We first derive general results for additively separable preferences and general productivity distributions, and...

This paper develops a two-country, optimising, sticky price model of real exchange rate determination in the 'new open macroeconomics' tradition which allows several different forms of deviation from purchasing power parity (PPP), both along the adjustment path and in the steady state. The model...

Equilibria and optima generally differ in imperfectly competitive markets. While this is well understood theoretically, it is unclear how large the welfare distortions are in the aggregate economy. Do they matter quantitatively? To answer this question, we develop a multi-sector monopolistic...

There is agreement within industrial organisation economics that an inverted U-shape relationship exists between the level of competition in an industry and the level of innovation in that industry. Thus, when consolidation changes the level of competition in an industry we might expect this to...