Making Good Decisions with Minimal Information: Simultaneous and Sequential Choice

The adaptive pressures facing humans and other animals to make decisions quickly can be met both by increasing internal information-processing speed and by minimizing the amount of information to be used. Here we focus on the latter effect and ask how, and how well, agents can make good decisions with a minimal amount of information, using two specific tasks as examples. When a choice must be made between simultaneously-available options, minimal information in the form of binary recognition (whether or not each item is recognized) can be used in the recognition heuristic to choose effectively. When options are encountered sequentially one at a time, minimal information as to whether or not each option is the best encountered so far is sufficient to guide agents using a simple search-cutoff rule to high performance along several choice criteria. Both of these examples have important economic as well as biological applications, and show the power of simple fast and frugal heuristics to produce good decisions with little information. This revised version was published online in August 2006 with corrections to the Cover Date.     

完全权益法与不完全权益法下合并报表方法之比较

合并报表编制方法可以分为从期初进行编制,也可以从期末进行编制。合并报表准则规定,合并时要将成本法调整为权益法后再行编制,由于完全权益法与不完全权益法的差异,会导致两种编制方法有不同的适应性。在完全权益法下编制合并报表适合从期初进行编制,在不完全权益法下编制合并报表适合从期末进行编制。     

Liquidity risk and arbitrage pricing theory

Classical theories of financial markets assume an infinitely liquid market and that all traders act as price takers. This theory is a good approximation for highly liquid stocks, although even there it does not apply well for large traders or for modelling transaction costs. We extend the classical approach by formulating a new model that takes into account illiquidities. Our approach hypothesizes a stochastic supply curve for a securitys price as a function of trade size. This leads to a new definition of a self-financing trading strategy, additional restrictions on hedging strategies, and some interesting mathematical issues.Received: 1 November 2003, Mathematics Subject Classification: 60G44, 60H05, 90A09JEL Classification: G11, G12, G13Umut Çetin: This work was performed while Dr. Çetin was at the Center for Applied Mathematics, Cornell UniversityPhilip Protter: Supported in part by NSF grant DMS-0202958 and NSA grant MDA-904-03-1-0092 The authors wish to thank M. Warachka and Kiseop Lee for helpful comments, as well as the anonymous referee and Associate Editor for numerous helpful suggestions, which have made this a much improved paper.     

Arrow's equivalency theorem in a model with neoclassical firms

Summary. In this paper we consider a two-period general equilibrium model with uncertainty and real assets as financial instruments. The novelty of the analysis is that real assets are the stocks of neoclassical firms, so that both returns and yields depend on anticipated spot goods prices (and, of course, the yield matrix may change rank with prices). Assuming that financial markets are potentially complete, we establish generic existence of financial equilibrium and prove that there exists a dense set of economies such that financial equilibria are efficient.Received: 19 April 2001, Revised: 23 April 2003, JEL Classification Numbers: C60, D51, G10, D60.I am extremely grateful to Dave Cass for drawing my attention to this problem and inspiring me to work on it as well as for many stimulating discussions. I also benefited from discussions with H. Polemarchakis, M. Stinchcombe, and A. Villanacci. I am thankful to the anonymous referee of the first versions of the paper for thoughtful comments and suggestions, and to participants of a recruiting seminar at the University of Texas at Austin (January 2001), the Conference on Economic Design SED 2000, Istanbul, Turkey (June 2000), and Inter-University Student Conference, New York University, New York (May 2000).     

用加重方法完全平衡平面机构惯性力的条件

在平面杆机构的设计中 ,惯性力的平衡是经常遇到的问题。本文经推导给出了用加重法完全平衡平面杆机构惯性力的条件     

基于有限理性的连锁董事战略分析

连锁董事是组织广泛采用的一种环境管理战略。那么，“连锁董事”存在的理论基础是什么？这在中国学才是一个比较新的研究领域，少有的几篇文献均以组织为重点展开探讨。国外相关方面研究较早，各学者从不同角度各砟重地加以诠释。为了更深刻、更全面地理解“连锁董事”的存在性，本文在评述西方理论的基础上，对各理论中合理因暑以整合，特别是考虑到现有理论仅从组织层或个人层出发，提出应从组织、个人和社会出发进行多层面分析。同时由于有理论过分强调理性决策，而现实中的组织、个人、社会决策都是有限理性的，应该把有限理性这一假设也纳入到分析框架中。因此，提出由连锁董事个人、连锁组织、社会三个层面的成本、收益分析及有限理性决策组成的新的分析框架。     

Collaboration,motivation, and the size of organizations

We present an analytical model of an organization that offers operational drivers of limits on team size. The model trades off benefits from collaborative problem solving against the disadvantages of diminishing motivation when groups get large. Collaboration is represented as parallel employee activity combined with frequent sharing of partial information, with a resulting superlinear performance increase over team size. Motivation is modeled by team members periodically setting an effort level either to contribute to the best of their ability or to “cruise”; at the minimum level not recognizable as shirking. Each individual decision is limited by bounded rationality based on team rewards, the time horizon of team interaction, and individual expectations about colleagues’ behavior. The decision collapses to a simple “barrier rule”;. Work hard when a certain “barrier percentage”; of team members work hard, and otherwise shirk. The influence of team size on this barrier percentage depends on the extent of benefits from collaboration: As long as performance increases quadratically with team size, the increased benefits resulting from collaboration exactly balance the temptation to shirk, with the barrier percentage approaching a fixed limit for large team sizes. As soon as the performance increase slows to anything less than quadratic, shirking eventually sets in and limits the possible size of the team. This implies that cooperation is sustainable in large organizational units, provided the problem‐solving processes used are powerful enough to ensure sufficient performance increases. Thus, effective problem‐solving methods are of double value, improving direct productivity and mitigating the social dilemma from team production. A manager should enlarge his or her organization up to the minimum of the limit set by the cooperation barrier and the exogenous performance limit.     

Payoff Assessments without Probabilities: A Simple Dynamic Model of Choice

We develop a model which reflects the tendency of people to simplify the decision problems they face. The decision maker chooses among alternate strategies only on the basis of the payoff she assesses she would obtain from them, and these assessments do not explicitly take into account her subjective judgements regarding the likelihood of alternate states of the world. At each stage, the decision maker chooses the strategy that she assesses to give the highest payoff. She updates her assessments adaptively. We show that such behavior leads to maxmin choices. We also consider the decision maker who experiences shocks. Journal of Economic Literature Classification Numbers: C7, D8.     

Strategic Interaction between Governments and Investors under Privatization Programs

This article analyses the strategic moves of governments and investors under privatization programs in a game‐theoretic context. In sequential‐move games of both perfect information and incomplete information, the best response of the strategic investors to observing a slow pace of privatization is to have a low participation in economic activity because of concerns over public policy credibility. This is true even if the government chooses to randomize its action to send mixed signals to the investors while adopting a slow pace of privatization for budgetary reasons. However, the outcome is Pareto inferior to a situation of phased but fast implementation of privatization programs and high private‐sector participation under plausible assumptions. Copyright © 2011 John Wiley & Sons, Ltd.