In this paper, I offer two ways in which firms can collude: secret monitoring and infrequent coordination. Such collusion is enforceable with intuitive communication protocols. I make my case in the context of a repeated Cournotoligopoly with flexible production, prices that follow a Brownian...

The cornerstone of cartel enforcement in the United States and elsewhere is a commitment to the lenient prosecution of early confessors. A burgeoning gametheoretical literature is ambiguous regarding the impacts of leniency. I develop a theoretical model of cartel behavior that provides...

We provide novel insights on the decentralization of optimal outcomes under monopolistic competition with nonseparable utility, variable demand elasticity, and endogenous firm heterogeneity. Relative to the unconstrained optimum, equilibrium firm selection is too weak, average firm size is too...

A buyer wishes to purchase a good from a seller who chooses a sequence of prices over time. Each period the buyer can also exercise an outside option, abandoning their search or moving on to another seller. We show there is a unique equilibrium in which the seller charges a constant price in...

We analyze the optimal policy of an antitrust authority towards horizontal mergers when merger proposals are endogenous and firms choose among alternative mergers. In our model, the optimal policy of an antitrust authority that seeks to maximize expected consumer surplus imposes a tougher...

We show that it is impossible to achieve collusion in a duopoly when (a) goods are homogenous and firms compete in quantities; (b) new, noisy information arrives continuously, without sudden events; and (c) firms are able to respond to new information quickly. The result holds even if we allow...

We formally characterize predatory pricing in a modern industry-dynamics framework that endogenizes competitive advantage and industry structure. As an illustrative example we focus on learning-by-doing. To disentangle predatory pricing from mere competition for efficiency on a learning curve we...

Quantifications of gains from trade in heterogeneous firm models assume that productivity is Pareto distributed. Replacing this assumption with log-normal heterogeneity retains some useful Pareto features, while providing a substantially better fit to sales distributions-especially in the left...