We review how realistic frictions in information and/or rationality arrest general equilibrium (GE) feedbacks. In one specification, we maintain rational expectations but remove common knowledge of aggregate shocks. In another, we replace rational expectations with Level-k Thinking or a smooth...

Industries with significant scale economies or learning-by-doing may come to be dominated by a single firm. Economists have studied how likely this is to happen, and whether it is efficient, using models where buyers are price or quantity takers, even though these industries are often also...

Many stylized facts of leverage, trading, and asset prices obtain in a frictionless general equilibrium model that features agents' heterogeneity in endowments and habit preferences. Our model predicts that aggregate debt increases in expansions when asset prices are high, volatility is low, and...

The foundations of incomplete contracts have been questioned using or extending the subgame perfect implementation approach of Moore and Repullo (1988). We consider the robustness of subgame perfect implementation to the introduction of small amounts of asymmetric information. We show that...

We study the efficiency of oligopoly equilibria in a model where firms compete over capacities and prices. The motivating example is a communication network where service providers invest in capacities and then compete in prices. Our model economy corresponds to a two-stage game. First, firms...

When a takeover is announced, the sum of the stock-market values of the firms involved often falls, and the value of the acquirer almost always does. Does this mean that takeovers do not raise the values of the firms involved? Not necessarily. We set up a model in which the equilibrium number of...

In the last forty or so years the U.S. financial system has morphed from a mostly insured retail deposit-based system into a system with significant amounts of wholesale short-term debt that relies on collateral, and in particular Treasuries, which have a convenience yield. In the new economy...

We study a flexible dynamic savings game in continuous time, where decision makers rotate in and out of power. These agents value spending more highly while in power creating a time-inconsistency problem. We provide a sharp characterization of Markov equilibria. Our analysis proceeds by...

Dynamically and statically optimal Pigouvian subsidies on durables will differ in a growing economy. For durables with positive externalities, such as sanitation, statically optimal subsidies will typically grow. However, in a dynamic game, governments can most cheaply induce optimal purchasing...