his book reviews recent progress in the theory of oligopoly and market leadership and provides new results on the theory of Stackelberg competition and Nash competition with strategic investment under endogenous entry. These theories are applied to models of competition in quantities, prices and...

I analyze the Renaissance art market in Italy through a unique dataset on primary commissions between 1285 and 1550. Hedonic regressions on the real price of paintings allow me to advance evidence that the art market was to a large extent competitive, and that an important determinant of...

We study platforms competing in commissions on revenues of sellers engaged in monopolistic competition, as the app providers on the app stores of iPhones and Android devices. Free entry of sellers on each platform generates multihoming superstars and a long tail of singlehoming sellers....

We develop a simple model of competition for the market that shows that, contrary to the Arrow view, endogenous entry threat in a market induces the average firm to invest less in R&D and the incumbent leader to invest more. We test these predictions with a Tobit model based on a unique dataset...