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Perfect Information (perfect + information)

Distribution by Scientific Domains
Business, Economics, Finance and Accounting63%
Engineering18%

Selected Abstracts

Pointing control design for a high precision flight telescope using quantitative feedback theory

INTERNATIONAL JOURNAL OF ROBUST AND NONLINEAR CONTROL, Issue 10 2001
Anthony E. Bentley
Abstract A pointing control system is developed and tested for a flying gimbaled telescope. The two-axis pointing system is capable of sub-microradian pointing stability and high accuracy in the presence of large host vehicle jitter. The telescope also has high agility , it is capable of a 50° retarget (in both axes simultaneously) in less than 2 s. To achieve the design specifications, high-accuracy, high-resolution, two-speed resolvers were used, resulting in gimbal-angle measurements stable to 1.5 µrad. In addition, on-axis inertial angle displacement sensors were mounted on the telescope to provide host-vehicle jitter cancellation. The inertial angle sensors are accurate to about 100 nrad, but do not measure low-frequency displacements below 2 Hz. The gimbal command signal includes host-vehicle attitude information, which is band-limited. This provides jitter data below 20 Hz, but includes a variable latency between 15 and 25 ms. One of the most challenging aspects of this design was to combine the inertial-angle-sensor data with the less perfect information in the command signal to achieve maximum jitter reduction. The optimum blending of these two signals, along with the feedback compensation were designed using Quantitative Feedback Theory. Copyright © 2001 John Wiley & Sons, Ltd. [source]

When Redistribution Leads to Regressive Taxation

JOURNAL OF PUBLIC ECONOMIC THEORY, Issue 4 2007
CYRIL HARITON
We introduce labor contracts in a framework of optimal redistribution: firms have some local market power and try to discriminate among heterogeneous workers. In this setting we show that if the firms have perfect information, i.e., they perfectly discriminate against workers and take all the surplus, the best tax function is flat. If firms have imperfect information, i.e., if they offer incentive contracts, then (under some assumptions) the best redistributive taxation is regressive. [source]

Research prioritization based on expected value of partial perfect information: a case-study on interventions to increase uptake of breast cancer screening

JOURNAL OF THE ROYAL STATISTICAL SOCIETY: SERIES A (STATISTICS IN SOCIETY), Issue 4 2008
N. J. Welton
Summary., We investigate whether Bayesian decision theory, in the form of expected value of partial perfect information (EVPPI) analysis, is a realistic and practical approach to research prioritization. We develop a simple cost-effectiveness analysis of breast cancer screening as a typical case-study, motivated by data from a cluster randomized 2 × 2 factorial trial of interventions to increase uptake. An EVPPI analysis is developed which shows that, on the basis of the evidence that was available beforehand, the trial was cost effective, but that after incorporating the results of the trial it would still be cost effective to carry out research that further reduced decision uncertainty. We identify key conceptual and technical issues: the relationship between the target interventions and the previous evidence, the distinction between variation and uncertainty and methods for correlated parameters. EVPPI methods have clear advantages over current methods of research prioritization, but we suggest that some specific sensitivity analyses are required before they can be used confidently in practice. These have limitations, and there is a need to develop robust methods to optimize research portfolios. [source]

A Generalized Oligopoly Model

METROECONOMICA, Issue 1 2002
Richard Watt
This paper generalizes and unifies the traditional quantity competition oligopoly models of Cournot and Stackelberg. Traditional oligopoly models predict that, under constant marginal costs, there will only be one market share (Cournot) or a single firm with a large market share and all others with the same market share (Stackelberg). Without altering the basic assumption set, in particular the assumptions of common marginal cost functions, perfect information and linear demand, the paper presents a general model that may be useful to explain many real-life situations of oligopoly competition, where many different market shares may coexist. Finally, it is shown that certain existing social welfare results are robust to the generalization. [source]

A differential dynamic programming algorithm for differential games

OPTIMAL CONTROL APPLICATIONS AND METHODS, Issue 1 2001
Theodore B. Trafalis
Abstract We develop and prove the convergence of a first-order differential dynamic programming algorithm for the solution of a zero-sum two-person differential game with perfect information. The algorithm extends a first-order strong variation algorithm for optimal control given by Mayne and Polak. Assuming separability of the Hamiltonian, we decompose the differential game problem into two control subproblems, C1 and C2. The objective is to determine a point (u*, v*) in U×V, where U and V are the control spaces for C1 and C2, respectively, that satisfies an integral form of Pontryagin's maximum principle for differential games. Copyright © 2001 John Wiley & Sons, Ltd. [source]

Price dispersion in a model of identical agents with perfect information

PACIFIC ECONOMIC REVIEW, Issue 1 2004
Zhiqi Chen
The driving force in the model is service capacity and congestion cost. Each firm chooses a service capacity. Customers of a firm bear a congestion cost which, for a fixed service capacity, is an increasing function of the number of customers served by this firm. We demonstrate that under certain conditions the combined profit of two firms and the total surplus are higher in a price-dispersion equilibrium than in a single-price equilibrium. [source]

PRICE-LEVEL DETERMINATION UNDER DISPERSED INFORMATION AND MONETARY POLICY,

THE JAPANESE ECONOMIC REVIEW, Issue 3 2006
KOSUKE AOKI
This paper considers the determination of aggregate price level under dispersed information. A Central Bank sets policy in response to its noisy measure of the price level, and each agent makes its decisions by observing a subset of data. Information revealed to the agents and the bank is determined endogenously. It is shown that the aggregate state of the economy is not revealed perfectly to anybody but this economy behaves as if it is a representative-agent economy in which the representative agent has perfect information while the Bank has partial information. The Bank's information set affects fluctuations in the price level through its effect on policy. [source]

CAN INEFFICIENT TRADERS CREATE VALUE?

THE JOURNAL OF FINANCIAL RESEARCH, Issue 4 2004
C. N. V. Krishnan
Abstract I examine the aggregate expected profit generated by informed traders of diverse ability in a competitive market. I assume that efficient traders get perfect information on asset values whereas inefficient traders get noisy information. In the presence of order size restrictions, I show that the aggregate expected profit generated by efficient and inefficient traders together can be higher than that generated by efficient traders alone. Thus, inefficient traders can create value in a constrained trading environment. [source]

Tradeable Emissions Permits, Emissions Taxes and Growth

THE MANCHESTER SCHOOL, Issue 4 2004
Bertrand Crettez
This paper uses a dynamic general equilibrium model with overlapping generations in order to analyse and to compare emissions taxes and tradeable emissions permits. Even in the context of a perfect environment, i.e. with perfect information, perfect competition,, it is shown that privately owned emissions permits have some disadvantages. An equilibrium with emissions permits would certainly be better than a laissez-faire equilibrium since it would entail a lower pollution level. However, it is far from clear that an economy with pollution permits would be preferable over an economy with emissions taxes. While in both cases pollution would be lower, growth would be higher in an economy with emissions taxes. This is because emissions permits divert saving from ,productive' resources and have a negative impact on capital accumulation. This happens whatever the way emissions taxes are redistributed. [source]

Product Safety Provision and Consumers' Information

AUSTRALIAN ECONOMIC PAPERS, Issue 4 2000
Stephan Marette
Economic mechanisms related to the provision of product safety are explored, with particular attention paid to the structure of consumers' information. The case of perfect information, of experience goods (for which consumers detect product safety after consumption) and of credence goods (where consumers cannot link a disease to a particular product consumed in the past) are explored. Imperfect competition is assumed in the supply sector. In the case of both perfect information and experience goods, market equilibrium is characterised by a less-than-socially optimal provision of safety, when the safety effort is costly. With credence goods, imperfect information leads to the absence of safety effort and to a market closure. Different types of public regulation aiming at increasing consumer protection and circumventing market failures are explored. Particular attention is paid to minimum safety standards, labels and liability enforcement. The relative efficiency of these instruments depends on the information structure. In the cases of perfect information and experience goods, a minimum safety standard can be an efficient instrument. Regulation is necessary but not sufficient to avoid market failure in the case of credence goods. [source]