共查询到20条相似文献,搜索用时 15 毫秒
1.
Wilfredo Leiva Maldonado 《Economic Theory》1999,14(2):473-478
Summary. In this paper I give a method for finding long-run-average policies in the undiscounted economic growth problem using approximations
by finite horizons. Required hypothesis is the strong interiority of T-horizon solutions.
Received: March 25, 1996; revised version: July 29, 1997 相似文献
2.
Summary. In this paper we study the behavior of optimal paths in dynamic programming models with a strictly convex return function.
Such a model has been investigated in Dawid and Kopel (1997) who assume that the growth of a renewable resource is governed
by a piecewise linear function. We prove that in their model the optimal cycles undergo the following qualitative changes
or bifurcations: a cycle of period n“bifurcates” into a cycle of period n+1 for increasing elasticity of the return function. We also show that under the assumption of a concave differentiable growth
function the qualitative properties of the optimal policy remain valid: oscillating behavior is optimal. Furthermore, we demonstrate
numerically that the period of a cyclic optimal path increases if the convexity of the return function (measured by the elasticity)
increases.
Received: January 22, 1997; revised version: October 13, 1997 相似文献
3.
Alan Beggs 《Economic Theory》2002,19(2):379-405
Summary. This paper studies the extent to which diffusion approximations provide a reliable guide to equilibrium selection results
in finite games. It is shown that they do for a class of finite games with weak learning provided that limits are taken in
a certain order. The paper also shows that making mutation rates small does not in general select a unique equilibrium but
making selection strong does.
Received: January 19, 2000; revised version: September 25, 2000 相似文献
4.
Summary. This note studies conditions under which sequences of state variables generated by discrete-time stochastic optimal accumulation
models have law of large numbers and central limit properties. Productivity shocks with unbounded support are considered.
Instead of restrictions on the support of the shock, an “average contraction” property is required on technology.
Received: August 27, 2001; revised version: January 9, 2002
RID="*"
ID="*"The author thanks John Creedy and Rabee Tourky for helpful comments, and the Economic Theory Center, University of Melbourne
for financial support. 相似文献
5.
Summary. We study decisions of subjects who are given an incentive to solve dynamic optimization problems with the structure of a
single-agent, one-sector, closed economy macroeconomic model. The decision task involves a sequence of choices of consumption
and investment levels. Treatment variables consist of the initial endowment of capital stock, the production technology available
to the economy, and the method of creating the structure of an infinite-horizon model. The study includes and contrasts data
from both American and Japanese participants. We find that whether over- or underinvestment relative to the optimum occurs
depends on the production technology, but not on the initial endowment of capital stock, nor the subject pool used, nor the
method of implementing the infinite horizon. Sudden episodes of maximal consumption called binges, which are always suboptimal, are widely observed.
Received: December 7, 1998; revised version: March 12, 1999 相似文献
6.
Massimiliano Amarante 《Economic Theory》2003,22(2):353-374
Summary. In each stage of a repeated game with private monitoring, the players receive payoffs and privately observe signals which
depend on the players' actions and the state of world. I show that, contrary to a widely held belief, such games admit a recursive
structure. More precisely, I construct a representation of the original sequential problem as a sequence of static games with
incomplete information. This establishes the ground for a characterization of strategies and, hence, of behavior in interactive-decision
settings where private information is present. Finally, the representation is used to give a recursive characterization of
the equilibrium payoff set, by means of a multi-player generalization of dynamic programming.
Received: February 11, 2002; revised version: July 22, 2002
RID="*"
ID="*" I am very grateful to In-Koo Cho, Larry Epstein, Denis Gromb, Stephen Morris, Paolo Siconolfi, Lones Smith and Max
Stinchcombe for several insights and suggestions. A referee's comments helped improving the exposition. Finally, I wish to
thank the participants to the seminars at MEDS, NYU, Columbia University, Caltech, UCLA, University of Rochester, University
of Texas-Austin, Northwestern Summer Microeconomics Conference 98, Summer in Tel Aviv 98, and NASM98. 相似文献
7.
Summary. Finding solutions to the Bellman equation often relies on restrictive boundedness assumptions. In this paper we develop a
method of proof that allows to dispense with the assumption that returns are bounded from above. In applications our assumptions
only imply that long run average (expected) growth is sufficiently discounted, in sharp contrast with classical assumptions
either absolutely bounding growth or bounding each period (instead of long run) maximum (instead of average) growth. We discuss
our work in relation to the literature and provide several examples.
Received: July 26, 2000; revised version: July 10, 2002
RID="*"
ID="*" I am specially grateful to Cuong Le Van and to anonymous referee for detecting an error in a previous version of this
paper and for suggestions that sensibly improved the paper. Comments and suggestions are also acknowledged to Michele Boldrin,
Raouf Boucekkine, Fabrice Collard, Tim Kehoe, Omar Licandro, and Luis Puch. I am also indebted to participants to the III
Summer School on Economic Theory held at the Universidade de Vigo, the Macroeconomics Workshop at the Universitat Autò}noma
de Barcelona, and the Econometrics Seminar at Tilburg University. Financial support from the Belgian government, under project
PAI P4/01, at the IRES-UCL, from a European Marie Curie fellowship, Grant HPMF-CT-1999-00410, at the CEPREMAP, and from IVIE
and Spanish Ministerio de Ciencia y Tecnología and FEDER, under project BEC2001-0535, at the Universidad de Alicante, is gratefully
acknowledged. 相似文献
8.
Aldo Rustichini 《Economic Theory》2002,20(4):677-702
Summary. We consider the extension of the classical problem of preference for flexibility to many periods. Preferences are defined
over sets of infinite paths of choices. The main result provides a set of axioms on preferences that yield an additive representation
over a subjective state space. This space is the set of preferences over choice today and feasible set tomorrow. The main
new axiom, stochastic dominance, is a stronger form of the assumption of monotonicity.
Received: September 11 2000; revised version: December 18, 2001 相似文献
9.
Summary. The dynamics of a stochastic, two–period principal–agent relationship is studied. The agent's type remains the same over
time. Contracts are short term. The principal designs the second contract, taking the information available about the agent
after the first period into account.
Compared to deterministic environments significant changes emerge: First, fully separating contracts are optimal. Second,
the principal has two opposing incentives when designing contracts: the principal ‘experiments,’ making signals more informative;
yet dampens signals, thereby reducing up–front payments. As a result, ‘good’ agents' targets are ratcheted over time.
Received: November 28, 2000; revised version: December 1, 2000 相似文献
10.
Michael Kosfeld 《Economic Theory》2002,20(2):321-339
Summary. The paper explores a model of equilibrium selection in coordination games, where agents from an infinite population stochastically
adjust their strategies to changes in their local environment. Instead of playing perturbed best-response, it is assumed that
agents follow a rule of ‘switching to better strategies with higher probability’. This behavioral rule is related to bounded-rationality models of Rosenthal (1989) and Schlag (1998). Moreover, agents stay
with their strategy in case they successfully coordinate with their local neighbors. Our main results show that both strict
Nash equilibria of the coordination game correspond to invariant distributions of the process, hence evolution of play is
not ergodic but instead depends on initial conditions. However, coordination on the risk-dominant equilibrium occurs with
probability one whenever the initial fraction contains infinitely many agents, independent of the spatial distribution of
these agents.
Received: March 14, 2000; revised version: June 21, 2001 相似文献
11.
Takashi Kamihigashi 《Economic Theory》2000,15(2):463-468
Summary. Ekeland and Scheinkman (1986) prove the necessity of a standard transversality condition under certain technical conditions.
Their result is one of the most powerful on the necessity of a transversality condition currently available in the literature,
and their proof involves numerous estimations and relies on Ekeland's variational principle and Fatou's lemma. This note relaxes
some of their assumptions and provides a simple proof that uses neither Ekeland's principle nor a convergence result like
Fatou's lemma.
Received: April 24, 1998; revised version: September 8, 1998 相似文献
12.
We show that range convexity of beliefs, a `technical' condition that appears naturally in axiomatizations of preferences
in a Savage-like framework, imposes some unexpected restrictions when modelling ambiguity averse preferences. That is, when
it is added to a mild condition, range convexity makes the preferences collapse to subjective expected utility as soon as
they satisfy structural conditions that are typically used to characterize ambiguity aversion.
Received: February 25, 2000; revised version: April 17, 2000 相似文献
13.
Makoto Shimoji 《Economic Theory》2002,19(3):637-648
Summary. We first consider money-burning games studied by Ben-Porath and Dekel [6]. We show that iterative weak dominance and extensive
form rationalizability yield the same unique outcome in this class of games. This result suggests that weak dominance captures the forward induction logic implied by extenisve
form rationalizability. Next, we consider an example of entry model by Arvan [1] to demonstrate the power of forward induction.
In this example, despite the presence of multiple equilibria, forward induction chooses a unique outcome.
Received: January 25, 2000; revised version: January 5, 2001 相似文献
14.
Koji Shimomura 《Economic Theory》1999,14(2):501-503
Summary. Based on some elementary results on duality, the paper proposes a much simpler way of deriving the class of non-homothetic
CES production functions which was derived as a solution to a partial differential equation that defines the elasticity of
substitution.
Received: February 11, 1998; revised version: April 28, 1998 相似文献
15.
Summary. We study the implications of optimal dynamic contracts in private information environments for fluctuations in effort and
employment across time and productivity states. To this end, we incorporate temporary layoffs and permanent separations as
well as on-the-job effort variations into a dynamic model of moral hazard. We consider two different “commitment” environments.
In a “full commitment” environment, although the firm can temporarily lay a worker off, neither party can dissolve the contractual
relationship once it has been initiated. On the other hand, in a “limited commitment” environment, both parties can dissolve
the relationship at the beginning of any period in order to pursue an outside option.
We use our model to study the implications of optimal contracts for incentives, employment histories, layoffs and separations
across full information, full commitment and limited commitment settings. We compute solutions to the relevant principal-agent
problems, endogenously determining the set of states in which separations occur and the domain of the firm's value function,
as well as the value function itself.
Received: February 28, 2000; revised version: January 21, 2001 相似文献
16.
Youngse Kim 《Economic Theory》1999,13(2):365-375
Summary. The paper studies the evolution of cooperation when satisficing players repeatedly play a symmetric two-by-two game of common
interest. We show that if initial aspiration levels are sufficiently close to the efficient payoff and aspiration adjusts
at a sufficiently slow speed then the unique long run state will be the efficient outcome. In the special case of coordination
games, the more tension there is between payoff dominance and risk dominance, the longer it takes for the system to lock into
the payoff dominant outcome.
Received: June 23, 1997; revised version: November 19, 1997 相似文献
17.
Robert J. Aumann 《Economic Theory》2003,21(2-3):233-239
Summary. Evidence is adduced that the sages of the ancient Babylonian Talmud, as well as some of the medieval commentators thereon,
were well aware of sophisticated concepts of modern theories of risk-bearing.
Received: April 10, 2002; revised version: May 7, 2002
RID="*"
ID="*"Presented at the Institute for Mathematical Studies in the Social Sciences-Economics, Stanford University, August 4,
1981. Subsequent to that presentation, the author's attention was drawn to an article by Zvi Ilani, “Models in the Economics
of Uncertainty: The Cost of Concluding a Conditional Contract, according to the Talmud and the Halachic Literature,” Iyunim Bekalkala (Investigations in Economics), The Israel Association for Economics, Jerusalem, Nissan 5740 (April 1980), 246–261 (in Hebrew). Inter alia, Ilani treats
the Talmudic passage that forms the subject of this paper, and provides a fairly comprehensive review of the medieval commentaries
thereon; undoubtedly, he was the first to recognize in print the relevance of this passage to modern economic theories of
uncertainty. It is not clear, though, whether or not his understanding of the passage agrees with ours. The current paper
appeared in January 2002 in the Research Bulletin Series of the Research Center on Jewish Law and Economics, Department of
Economics, Bar Ilan University. 相似文献
18.
Closed-loop equilibrium in a multi-stage innovation race 总被引:1,自引:0,他引:1
Kenneth L. Judd 《Economic Theory》2003,21(2-3):673-695
Summary. We examine a multistage model of an R&D race where players have multiple projects. We also develop perturbation methods for
general dynamic games that can be expressed as analytic operators in a Banach space. We apply these perturbation methods to
solve races with a small prize. We compute second-order asymptotically valid solutions for equilibrium and socially optimal
decisions to determine qualitative properties of equilibrium. We find that innovators invest relatively too much on risky
projects. Strategic reactions are ambiguous in general; in particular, a player may increase expenditures as his opponent
moves ahead of him.
Received: January 3, 2002; revised version: June 14, 2002
RID="*"
ID="*" This is the final version of Judd (1985). The author gratefully acknowledges the comments of anonymous referees, Paul
Milgrom, seminar participants at Northwestern University, the University of Chicago, the 1984 Summer Meetings of the Econometric
Society, University of California at Berkeley, Stanford University, and Yale University, and the financial support of the
National Science Foundation (SES-8409786, SES-8606581) 相似文献
19.
Pamela Labadie 《Economic Theory》1998,12(3):621-648
Summary. Private information and costly state verification often result in credit rationing in models with smooth investment, affecting
both loan size and total investment. The optimal contract is derived in a dynamic stochastic growth model with capital for
two types of models: one with symmetric information and the other with asymmetric information and costly state verification.
When all information is observed costlessly, the equilibrium optimal contract provides complete insurance to risk-averse savers
against aggregate fluctuations. When information is asymmetric and there is costly state verification, the equilibrium optimal
contract provides only partial insurance against aggregate shocks. The extent of insurance is measured by the marginal rate
of transformation of consumption between borrowers and lenders which is closely linked to the user cost of capital. The deadweight
monitoring costs create a wedge between a borrower's cost of capital and a lender's stochastic discount factor, with two results:
(i) fluctuations in the user cost of capital provides a mechanism by which aggregate shocks can be␣propagated; (ii) the distribution
of capital's share of output among borrowers, lenders, and monitoring costs varies even if capital's share is constant. Capital
market frictions not only amplify aggregate fluctuations but also generate cross-sectional fluctuations that may not be observable
in aggregate data.
Received: November 17, 1997; revised version: April 20, 1998 相似文献
20.
Salvador Ortigueira 《Economic Theory》2000,16(1):43-62
Summary. The main goal in this paper is to analyze an economic model of endogenous growth where human capital accumulation acts as
the engine propelling economic activity. The added ingredient in our model is that agents derive utility from consumption
and leisure, where leisure is defined as the amount of time devoted to those activities augmented by the level of education.
Under regular conditions we show that there is a unique globally stable balanced growth path. We also provide a characterization
of the behavior of our economic variables along the transition.
Received: May 26, 1998; revised version: September 9, 1999 相似文献