Corporate Control and the Stock Market

This paper studies a general equilibrium model with an investor controlled firm. Shareholders can vote on the firm’s production plan in an assembly. Prior to that they may trade shares on the stock market. Since stock market trades determine the distribution of votes, trading is strategic. There is always an equilibrium, where share trades lead to owners deciding for competitive behavior, but there may also be equilibria, where monoplistic behavior prevails.Corporate governance, general equilibrium, objective function of the firm, shareholder voting, stock markets.

On the Non-Cooperative Foundations of Cooperative Bargaining

In this note we challenge the non-cooperative foundations of cooperative bargaining solutions on the grounds that the limit operation for approaching a frictionless world is not robusto We show that when discounting almost ceases to play a role, any individually rational payoff can be supported by some subgame perfect equilibrium. To select the "correct" point imposes excessive informationaL requirements on the analyst.Subgame Perfection Rubinstein Game

Cross-Ownership Among Firms: Some Determinants of the Separation of Ownership from Control

This paper demonstrates that the current literature on cross-ownership among firms underestimates the true degree of separation between cash flow rights and voting rights. We use accounting identities to define coefficients of control, such that any (direct or indirect) control of a firm may be identified using these coefficients. This procedure is sufficient to show that under cross-ownership the voting rights associated with ownership are typically underestimated. We demonstrate by example that control and ownership of dividend rights may be entirely separated, and that multiple equilibria may exist in economies with cross ownership.Cross-ownership, Ownership and control, Corporate governance

Order-Driven Markets are Almost Competitive

This article studies a market game under uncertainty in which agents may submit multiple limit and market orders. When agents know their preferences at all states, the competitive equilibrium can be supported as a Nash equilibrium of the market game, that is, agents behave as if they were price takers. Therefore, if the associated competitive economy has a fully revealing rational expectations equilibrium, then so does the market game. This resolves the puzzle that agents behave as if prices were given, even though prices aggregate private information, at least for this “private values” case. Necessary conditions for Nash equilibrium show that the resulting allocation cannot deviate too far from a competitive equilibrium. When agents do not know their preferences at some states, though, a characterization result shows that the Nash equilibria of the market game tend to be far from competitive. (author's abstract

Trees and Decisions

The traditional model of sequential decision making, for instance, in extensive form games, is a tree. Most texts define a tree as a connected directed graph without loops and a distingueshed node, called the root. But an abstract graph is not a domain for decision theory. Decision theory perceives of acts as function from states to consequences. Sequential decisions, accordingly, get conceptualized by mappings from sets of states to sets of consequences. Thus, the question arises whether a natural definition of a tree can be given, where nodes are sets of states. We show that, indeed, trees can be defined as specific collections of sets. Without loss of generality the elements of these sets can be interpreted as representing plays. Therefore, the elements can serve as states and consequences at the same time.

Trees and Extensive Forms

This paper addresses the question of what it takes to obtain a well-de?ned extensive form game. Without relying on simplifying ?niteness or discreteness assumptions, we characterize the class of game trees for which (a) extensive forms can be de?ned and (b) all pure strategy combinations induce unique outcomes. The generality of the set-up covers “exotic” cases, like stochastic games or decision problems in continuous time (di?erential games). We ?nd that the latter class ful?lls the ?rst, but not the second requirement.

Trees and Decisions

The traditional model of sequential decision making, for instance, in extensive form games, is a tree. Most texts de?ne a tree as a connected directed graph without loops and a distinguished node, called the root. But an abstract graph is not a domain for decision theory. Decision theory perceives of acts as functions from states to consequences. Sequential decisions, accordingly, get conceptualized by mappings from sets of states to sets of consequences. Thus, the question arises whether a natural de?nition of a tree can be given, where nodes are sets of states. We show that, indeed, trees can be de?ned as speci?c collections of sets. Without loss of generality the elements of these sets can be interpreted as representing plays. Therefore, the elements can serve as states and consequences at the same time.Decision under uncertainty, Extensive form games, Trees

The Simple Geometry of Perfect Information Games

Perfect information games have a particularly simple structure of equilibria in the associated normal form. For generic such games each of the finitely many connected components of Nash equilibria is contractible. For every perfect information game there is a unique connected and contractible component of subgame perfect equilibria. Finally, the graph of the subgame perfect equilibrium correspondence, after a very mild deformation, looks like the space of perfect information extensive form games.Perfect information, Subgame perfection, Equilibrium correspondence

Strategic Pricing, Signalling, and Costly Information Acquisition

Consider a market where an informed monopolist sets the price for a good or as set with a value unknown to potential buyers. Upon observing the price, buyers may pay some cost for information about the value before deciding on purchases. To restrict buyer beliefs we generalize the idea of the Cho--Kreps ``intuitive criterion''. Then there is no separating equilibrium with fully revealing prices. Yet, as the cost of information acquisition becomes small, the equilibrium approaches the full information outcome and prices become perfectly revealing.quality uncertainty; price signalling; information acquisition

On the Non-Cooperative Foundations of Cooperative Bargaining

In this note we challenge the non-cooperative foundations of cooperative bargaining solutions on the grounds that the limit operation for approaching a frictionless world is not robusto We show that when discounting almost ceases to play a role, any individually rational payoff can be supported by some subgame perfect equilibrium. To seLect the "correct" point imposes excessive informationaL requirements on the anaLyst