This paper presents a model of cumulative innovation where firms are heterogeneous in their research ability. We study the optimal reward policy when the quality of the ideas and their subsequent development effort are private information. The optimal assignment of property rights must counterbalance the incentives of current and future innovators. The resulting mechanism resembles a menu of patents that have infinite duration and fixed scope, where the latter increases in the value of the idea. Finally, we provide a way to implement this patent menu by using a simple buyout scheme: The innovator commits at the outset to a price ceiling at which he will sell his rights to a future inventor. By paying a larger fee initially, a higher price ceiling is obtained. Any subsequent innovator must pay this price and purchase its own buyout fee contract.

Innovative activities have public good characteristics in the sense that the cost of producing the innovation is high compared to the cost of producing subsequent units. Moreover, knowledge of how to produce subsequent units is widely known once the innovation has occurred and is, therefore, non-rivalrous. The main question of this paper is whether mechanisms can be found which exploit market information to provide appropriate incentives for innovation. The ability of the mechanism designer to exploit such information depends crucially on the ability of the innovator to manipulate market signals. We show that if the innovator cannot manipulate market signals, then the efficient levels of innovation can be implemented without deadweight losses–for example, by using appropriately designed prizes. If the innovator can use bribes, buybacks, or other ways of manipulating market signals, patents are necessary.

Recent developments in the theory of economies with private information permit a re-examination of the issues raised in the "real bills-quantity theory" debate. A model is developed here in which there are banks, in which fiat money is present, and in which agents possess private information. Two regulatory regimes are then considered. In the first, banks are essentially unregulated. In the second, banks face 100 percent reserve requirements. Issues related to existence and optimality of equilibrium are addressed, and problems with existence are given an interpretation in terms of the "stability" of the banking system. Existence (stability) problems which arise under laissez-faire banking can be rectified by a 100 percent reserve requirement. However, unless there is private information regarding access to investment opportunities, there are typically better ways to accomplish this. Finally, it is shown that even in the presence of 100 percent reserve requirements banks are not simply "money warehouses." Bank deposits and money bear different (real) return streams, even under 100 percent reserves.

"Summary of Recommendations: . . . Repeal present control by the System over interest rates that member banks may pay on time deposits and present prohibition of interest payments by member banks on demand deposits." Milton Friedman (1960, p. 100) "I conclude that the over-all monetary effects of ceiling regulations are small and easy to neutralize by traditional monetary controls. The allocative and distributive effects are, however, unfortunate. The root of the policy was an exaggerated and largely unnecessary concern for the technical solvency of savings and loan associations." James Tobin (1970, p. 5) The regulation of deposit interest rates has received little support from economists. The same is true for the original rationale for such regulation: that bank competition for deposits generates inherent "instability" in the banking system. This paper develops an "adverse selection" model of banking in which this rationale is correct. Moreover, in this model instability in the banking system can arise despite the presence of a "lender of last resort," and despite the absence of any need for "deposit insurance." However, in the world described, the regulation of deposit interest rates is shown to be an appropriate response to "instability" in the banking system. Finally, it is argued that "adverse selection" models of deposit interest rate determination can confront a number of observed phenomena that are not readily explained in other contexts.

The effects on ex ante optima of a lag in seeing monetary realizations are studied using a matching model of money. The main new ingredient in the model is meetings in which producers have more information than consumers. A consequence is that increases in the amount of money that occur with small enough probability can have negative impact effects on output, because it is optimal to shut down trade in such low probability meetings rather than have lower output when high probability realizations occur. The information lag also produces prices that do not respond much to current monetary realizations.

This paper examines the sets of feasible allocations in a large class of economic environments in which commitment is impossible (the standard definition of feasibility is adapted to take account of the lack of commitment). The environments feature either memory or money. Memory is defined as knowledge on the part of an agent of the full histories of all agents with whom he has had direct or indirect contact in the past. Money is defined as an object that does not enter preferences or production and is available in fixed supply. The main proposition proves that any allocation that is feasible in an environment with money is also feasible in the same environment with memory. Depending on the environment, the converse may or may not be true. Hence, from a technological point of view, money is equivalent to a primitive form of memory.

A model of credit rationing based on asymmetrically informed borrowers and lenders is developed. In this context, sufficient conditions are derived for an appropriate government policy response to credit rationing to be a continuously open discount window. It is also demonstrated that such a policy can be deflationary, and that given a commitment to operate in this way, the monopoly issue of liabilities can Pareto dominate their competitive issuance.

A model with private information is constructed that supports conventional arguments for a government monopoly in supplying circulating media of exchange. The model also yields predictions, including rate-of-return dominance of circulating media of exchange, that are consistent with observations from free banking regimes and fiat money regimes. In a laissez faire banking equilibrium, fiat money is not valued, and the resulting allocation is not Pareto optimal. However, if private agents are restricted from issuing circulating notes, there exists an equilibrium with valued fiat money that Pareto dominates the laissez faire equilibrium and is constrained Pareto optimal.

In a finite-trader version of the Diamond-Dybvig (1983) model, the symmetric, ex-ante efficient allocation is implementable by a direct mechanism (i.e., each trader announces the type of his own ex-post preference) in which truthful revelation is the strictly dominant strategy for each trader. When the model is modified by formalizing the sequential-service constraint (cf. Wallace, 1988), the truth-telling equilibrium implements the symmetric, ex-ante efficient allocation with respect to iterated elimination of strictly dominated strategies.

This paper surveys implementation theory when players have incomplete or asymmetric information, especially in economic environments. After the basic problem is introduced, the theory of implementation is summarized. Some coalitional considerations for implementation problems are discussed. For economies with asymmetric information, cooperative games based on incentive compatibility constraints or Bayesian incentive compatible mechanisms are derived and examined.

General competitive analysis is extended to cover a dynamic, pure-exchange economy with privately observed shocks to preferences. In the linear, infinite-dimensional space containing lotteries we establish the existence of optima, the existence of competitive equilibria, and that every competitive equilibrium is an optimum. An example illustrates that rationing and securities with contrived risk have an equilibrium interpretation.

"Financial intermediary-coalitions" (WP 272) replaces "Financial intermediaries" (WP 231) and "Father of financial intermediary-coalitions" (WP 250).

"Financial intermediary-coalitions" (WP 272) replaces "Financial intermediaries" (WP 231) and "Father of financial intermediary-coalitions" (WP 250).

"Financial intermediary-coalitions" (WP 272) replaces "Financial intermediaries" (WP 231) and "Father of financial intermediary-coalitions" (WP 250).

We develop an equilibrium concept in the Debreu (1954) theory of value tradition for a class of adverse selection economies which includes the Spence (1973) signaling and Rothschild-Stiglitz (1976) insurance environments. The equilibrium exists and is optimal. Further, all equilibria have the same individual type utility vector. The economies are large with a finite number of types that maximize expected utility on an underlying commodity space. An implication of the analysis is that the invisible hand works for this class of adverse selection economies.

In this paper I develop continuous-time methods for solving dynamic principal-agent problems in which the agent’s privately observed productivity shocks are persistent over time. I characterize the optimal contract as the solution to a system of ordinary differential equations, and show that, under this contract, the agent’s utility converges to its lower bound—immiseration occurs. I also show that, unlike in environments with i.i.d. shocks, the principal would like to renegotiate with the agent when the agent’s productivity is low—it is not renegotiation-proof. I apply the theoretical methods I have developed and numerically solve this (Mirrleesian) dynamic taxation model. I find that it is optimal to allow a wedge between the marginal rate of transformation and individuals’ marginal rate of substitution between consumption and leisure. This wedge is significantly higher than what is found in the i.i.d. case. Thus, using the i.i.d. assumption is not a good approximation quantitatively when there is persistence in productivity shocks.

This paper surveys cooperative game theory when players have incomplete or asymmetric information, especially when the TU and NTU games are derived from economic models. First some results relating balanced games and markets are summarized, including theorems guaranteeing that the core is nonempty. Then the basic pure exchange economy is extended to include asymmetric information. The possibilities for such models to generate cooperative games are examined. Here the core is emphasized as a solution, and criteria are given for its nonemptiness. Finally, an alternative approach is explored based on Harsanyi’s formulation of games with incomplete information.

Previous authors have argued that the optimal monetary policy is contractionary. If buyers value consumption substantially more than sellers, there is some randomness and informational constraints make asset trading useful, we show that there is an incentive compatible expansionary policy that dominates all incentive compatible contractionary policies.

We study the quantitative properties of constrained efficient allocations in an environment where risk sharing is limited by the presence of private information. We consider a life cycle version of a standard Mirrlees economy where shocks to labor productivity have a component that is public information and one that is private information. The presence of private shocks has important implications for the age profiles of consumption and income. First, they introduce an endogenous dispersion of continuation utilities. As a result, consumption inequality rises with age even if the variance of the shocks does not. Second, they introduce an endogenous rise of the distortion on the marginal rate of substitution between consumption and leisure over the life cycle. This is because, as agents age, the ability to properly provide incentives for work must become less and less tied to promises of benefits (through either increased leisure or consumption) in future periods. Both of these features are also present in the data. We look at the data through the lens of our model and estimate the fraction of labor productivity that is private information. We find that for the model and data to be consistent, a large fraction of shocks to labor productivities must be private information.

There is now an extensive literature regarding the efficient design of incentive mechanisms in dynamic environments. In this literature, there are no exogenous links across time periods because either privately observed shocks are assumed time independent or past private actions have no influence on the realizations of current variables. The absence of exogenous links across time periods ensures that preferences over continuation contracts are common knowledge, making the definition of incentive compatible contracts at a point in time a simple matter. In this paper, we present general recursive methods to handle environments where privately observed variables are linked over time. We show that incentive compatible contracts are implemented recursively with a threat keeping constraint in addition to the usual temporary incentive compatibility conditions.

A model of a labor market is developed in which agents possess private information about their marginal products. As a result, involuntary unemployment may arise as a consequence of attempts by firms to create appropriate self-selection incentives. Moreover, employment lotteries may arise for the same reason despite the fact that, in equilibrium, there is no uncertainty in the model. When employment is random, this is both privately and socially desirable. Finally, it is shown that the unemployment that arises is consistent with (a) pro-cyclical aggregate real wages and productivity, (b) employment that fluctuates (at individual and aggregate levels) much more than real wages.

A model of a "real" business cycle is produced in which labor market participants possess private information. A class of economies is considered in which interesting cycles cannot arise without private information. A methodology adapted from Kydland and Prescott (1982) is then employed to show that models based on private information can empirically confront salient features of postwar U.S. business cycles. Moreover, this can be done in a way which is consistent with existing microeconomic evidence on wages and labor supply. Finally, it is shown that the important features of the model related to private information are fairly general.