Estimating market power is often complicated by the lack of reliable measures of marginal cost. Instead, policy-makers often rely on other summary statistics of the market, thought to be correlated with price cost margins - such as concentration ratios or the HHI. In many industries, these...

This paper develops a theory of oligopoly and markups in general equilibrium. Firms compete in a network of product market rivalries that emerges endogenously out of the characteristics of the products and services they supply. My model embeds a novel, highly tractable and scalable demand system...

Bank market power shapes firm investment and financing dynamics and hence affects the transmission of macroeconomic shocks. Motivated by a secular increase in the concentration of the US banking industry, I study bank market power through the lens of a dynamic general equilibrium model with...

Mark-up cyclical behaviour is relevant in determining the size of government spending multiplier on output. While theoretical literature priviliged the counteryclical hypothesis, empirical evidence is far from being conclusive. Based on seminal Rotemberg and Saloner (1986) contribution, we build...

We study how the interaction of market power and nominal price rigidity influences inflation dynamics. We formulate a tractable model of oligopolistic competition and sticky prices and derive closed-form expressions for the pass-through of idiosyncratic and common cost shocks to firms' prices....

This paper examines a homogeneous-good Bertrand-Edgeworth oligopoly model to explore the role of firm size and number in pricing. We consider the price impact of merger, break up, investment, divestment, entry and exit. A merger leads to higher prices only when it increases the size of the...

This is a survey of the economic principles that underlie antitrust law and how those principles relate to competition policy. We address four core subject areas: market power, collusion, mergers between competitors, and monopolization. In each area, we select the most relevant portions of...