205 research outputs found
On the informed principal model with common values
No full textInternational audienceAbstract In the informed principal model with common values, I provide conditions that allow for the characterization of the set of equilibria of the game in which the principal makes a take‐it‐or‐leave‐it offer of a mechanism to the agent. I further examine if and when restriction to direct revelation mechanisms is without loss of generality. Last, I provide clear guidelines for solving economic applications, such as insurance, procurement, security design, and bilateral trading, of the informed principal model. The results are compared with and shown to significantly differ from those obtained in Maskin and Tirole (1992)
Optimal Trading for an Informed Seller
No full textA seller with perfect monopoly power trades an indivisible object with a buyer. Both the seller's and the buyer's valuations for the object depend on its quality, which is privately known by the seller. Moreover, the seller has perfect information about the buyer's valuation for each quality. Even though posting a fixed price is ex ante optimal, it might not be interim individually rational and hence not necessarily implementable. The set of interim optimal allocations is charac-terised by solving a parametric linear maximisation program. These allocations might differ from simple price-posting. If the seller offers a menu of contracts, then allocations that are not interim optimal can be supported as equilibrium allocations. However, this sub-optimality result seems not to be robust if there are at least two buyers who can counter-offer menus of contracts after the seller's offer. In that case, an allocation is an equilibrium allocation if and only if it is interim optimal
The effects of redistributive taxation in credit markets with adverse selection
No full textInternational audienc
On the Informed Principal Model with Common Values *
No full textThis paper reconsiders the general informed principal model with unilateral private information and common values. First, it identifies some fundamental properties of the Rothschild-Stiglitz-Wilson (RSW) allocation (i.e., the undominated for the principal allocation within the set of incentive compatible and individually rational for the agent type by type allocations). Based on these properties: (i) it constructs a more robust, and perhaps simpler, proof of the "if part" of Theorem 1 (i.e., the main result) of Maskin and Tirole (1992), and, (ii) it establishes that if the principal is restricted to offering mechanisms in which only she makes announcements (e.g., direct revelation mechanisms), then the conclusion of that theorem holds even in environments in which the RSW allocation is not interim efficient relative to any non-degenerate beliefs. Second, it provides a sufficient condition that allows for the complete charac-terisation of the set of equilibrium allocations even in environments in which single-crossing is not satisfied
On Signalling and Screening in Markets with Asymmetric Information
No full textThe two games that are typically used to model markets with asymmetric information are the signalling game and the screening game. In the signalling game, an equilibrium may not be efficient because of the arbitrariness of off-the-equilibrium-path beliefs. In the screening game, a pure-strategy Nash equilibrium may fail to exist because of " cream-skimming " deviations. Perhaps surprisingly, I show how equilibrium generically exists and is efficient in a game that combines signalling and screening. The signalling part assures the existence of equilibrium, whereas the screening part prevents non-efficient allocations from being supported as equilibrium allocations
Competitive Markets with Asymmetric Information II: Entry, Incumbent's Vulnerability and Efficiency
No full textA More General Definition of Equilibrium in Markets with Adverse Selection
No full textI provide a general definition of equilibrium in markets with adverse selection. An equilibrium is defined as a menu of contracts that makes non-negative aggregate profits such that there exists no other menu that includes it as a subset and makes strictly positive aggregate profits. I show that every efficient menu of contracts is also an equilibrium menu of contracts. Furthermore, I characterise a general sufficient condition under which every equilibrium menu of contracts is efficient, restoring that way the First Fundamental Theorem of Welfare Economics. I provide two possible interpretations for this new definition
Optimal Ex Post Risk Adjustment in Markets with Adverse Selection *
No full textThis paper studies general health insurance markets. It proposes an ex post risk adjustment scheme that discourages risk selection and promotes efficient competition. Under the proposed risk adjustment scheme, the regulator engages in transfers that are conditional on the ex post profits of insurers. The risk adjustment scheme is entirely budget balanced, as it does not call for government subsidies, and requires the regulator to hold minimal information to implement it. Equilibrium is shown to exist and be efficient in any environment with a finite number of types and states even if single-crossing is not satisfied
- …
