Realizable Utility Maximization as a Mechanism for the Stability of Competitive General Equilibrium in a Scarf Economy

A competitive general equilibrium (CGE) is a Pareto-optimal allocation, but it is not always stable under the mechanism of the tâtonnement process. How to drive an economy to the CGE and maintain its stability remains to be an issue with a high intellectual interest. In this article, using the celebrated counterexample of the Scarf economy, we first provide an intuitive and explicit explanation to analyze why the CGE is unstable under the tâtonnement process. Then a novel mechanism, called the realizable utility maximization mechanism (RUMM), is proposed in which the price of a product is adjusted not according to the excess demand as in the standard tâtonnement process, but according to the potential utility of the individuals owning the product. It is found that the RUMM can maintain the stability of the CGE even in the Scarf economy, and can shed light on the role of social learning in stabilizing the Scarf economy as we have learned from the literature of agent-based non-tâtonnement models.

     

Resource allocation in decentralised computational systems: an evolutionary market-based approach

We present a novel market-based method, inspired by retail markets, for resource allocation in fully decentralised systems where agents are self-interested. Our market mechanism requires no coordinating node or complex negotiation. The stability of outcome allocations, those at equilibrium, is analysed and compared for three buyer behaviour models. In order to capture the interaction between self-interested agents, we propose the use of competitive coevolution. Our approach is both highly scalable and may be tuned to achieve specified outcome resource allocations. We demonstrate the behaviour of our approach in simulation, where evolutionary market agents act on behalf of service providing nodes to adaptively price their resources over time, in response to market conditions. We show that this leads the system to the predicted outcome resource allocation. Furthermore, the system remains stable in the presence of small changes in price, when buyers’ decision functions degrade gracefully.     

Keynesian Dynamics and the Wage–Price Spiral: Identifying Downward Rigidities

We develop a constrained bivariate switching model to explore empirically the behavior of wage and price Phillips-curves for high- and low-inflation regimes. Using this switching regression technique with a structural simultaneous equations model of Phillips curves, we identify significant lower floors for wage and price inflation. We interpret these lower floors as the relevant downward rigidity for wages and prices. Such floors imply that the adverse real-wage adjustment mechanism that can be identified in the high-inflation regime may disappear in the low-inflation regime, where money-wage inflation and price inflation, and thus real-wage movements, may become rigid. Consequently, the economy may be stabilized then, but trapped in a long period of stagnation in such a low-inflation situation. Such properties of kinked wage and price Phillips-curves are thus important and could also be of help to break another important destabilizing feedback channel, the Fisher debt deflation mechanism, according to which economies, in which highly indebted firms are unable to prevent price deflation, will experience severe crisis or even economic breakdown if the resulting deflationary spiral cannot be stopped.JEL classifications: C39; E24; E31; E32; J30     

基于博弈论的认知无线电频谱分配

为了解决频谱分配中的授权用户定价博弈问题,根据博弈论中的Bertrand均衡理论,提出了基于Bertrand模型的授权用户信道价格竞争的动态博弈算法。分析了稳定的纳什均衡解与速率调整参数的关系,用控制理论中阶跃函数研究价格无震荡博弈过程,提出了三值法确定阶跃响应参数。仿真结果表明,当数率调整参数在小于0.04时,可以获得稳定的信道价格;同时,验证了用阶跃函数分析无震荡博弈过程的可行性,方便授权用户快速实时定价,带来更大的经济效益。     

约束非线性系统稳定经济模型预测控制

考虑约束非线性系统,提出一种新的具有稳定性保证的经济模型预测控制（Economic model predictive control,EMPC）策略.由于经济性能指标的非凸性和非正定性,引入关于经济最优平衡点的正定辅助函数.利用辅助函数的最优值函数定义原始EMPC优化问题的稳定性约束.应用终端约束集、终端代价函数和局部控制器三要素,建立闭环系统关于经济最优平衡点的渐近稳定性和渐近平均性能.进一步,结合多目标理想点概念,将提出的控制策略用于多个经济性能指标的优化控制,得到稳定多目标EMPC策略.最后,以连续搅拌反应器为例,比较仿真结果验证本文策略的有效性.     

Dynamic pricing by software agents

We envision a future in which the global economy and the Internet will merge, evolving into an information economy bustling with billions of economically motivated software agents that exchange information goods and services with humans and other agents. Economic software agents will differ in important ways from their human counterparts, and these differences may have significant beneficial or harmful effects upon the global economy. It is therefore important to consider the economic incentives and behaviors of economic software agents, and to use every available means to anticipate their collective interactions. We survey research conducted by the Information Economies group at IBM Research aimed at understanding collective interactions among agents that dynamically price information goods or services. In particular, we study the potential impact of widespread shopbot usage on prices, the price dynamics that may ensue from various mixtures of automated pricing agents (or “pricebots”), the potential use of machine-learning algorithms to improve profits, and more generally the interplay among learning, optimization, and dynamics in agent-based information economies. These studies illustrate both beneficial and harmful collective behaviors that can arise in such systems, suggest possible cures for some of the undesired phenomena, and raise fundamental theoretical issues, particularly in the realms of multi-agent learning and dynamic optimization.     

The Neutrality of Money Revisited with a Bottom-Up Approach: Decentralisation,Limited Information and Bounded Rationality

In the mainstream top-down approach, money is neutral except with special assumptions. Intending to make money “essential”, random-matching models introduced decentralisation by considering pair-wise transactions. Nevertheless, in both cases top-level equilibrium constrains agents’ behaviour. Instead, here we use a bottom-up approach. In a competitive market, decentralised autonomous agents meet and exchange a commodity for money. Their decisions use minimal information. They are triggered by simple rules founded on a “satisficing” procedure and on a random decision process that simulates bounded rationality. The conclusions are, first, that non-monetary costs are essential to avoid collapse of the economy. Second, mainly “price setters” who are adequately satisfied achieve equilibrium protecting themselves by evolving advantages to avoid competition that is too tough. Third, and the most important conclusion is that money ceases to be neutral as soon as competition arises between individual firms.     

Mobilising information systems scholarship for a circular economy: Review,synthesis, and directions for future research

One of today's grand societal challenges is to replace the current ‘take‐make‐waste’ economic model with a circular economic model that allows a gradual decoupling of economic activities from the consumption of finite virgin resources. While circular economy (CE) scholars have long lauded digital technologies such as sensors, distributed ledgers, or platforms as key enablers, our own community has not fully explored the potentials of information systems (IS) for a CE. Considering recent technological advances in software and hardware and our history of helping address wicked challenges, we believe the time is ripe to mobilise IS scholarship for a CE. Our findings from an interdisciplinary literature review show that research has primarily examined IS potentials for increasing efficiency of isolated intra‐organisational processes while neglecting the larger sustainability potential of IS to establish circular material flows—that is, slow down and close material loops across entire product lifecycles. In response, we propose directions for IS research that develop our knowledge of how IS can help understand and enact circular material flows to intensify and extend use of products and components and recycle waste materials. Our directions offer pathways to building and evaluating the problem‐solution pairing that could characterise a prolific CE‐IS relationship.     

Modeling and analysis of the effects of QoS and reliability on pricing, profitability, and risk management in multiperiod grid-computing networks

In this paper we develop a network equilibrium model for optimal pricing and resource allocation in Computational Grid Network. We consider a general network economy model with Grid Resource Providers, Grid Resource Brokers and Grid Users. The proposed framework allows for the modeling and theoretical analysis of Computational Grid Markets that considers a non-cooperative behavior of decision-makers in the same tier of the grid computing network (such as, for example, Grid Resource Providers) as well as cooperative behavior between tiers (between Resource Providers and Grid Brokers). We introduce risk management into the decision making process by analyzing the decision-marker's reliability and quality of service (QoS) requirement. We analyze resource allocation patterns as well as equilibrium price based on demand, supply, and cost structure of the grid computing market network. We specifically answer the following questions with several numerical examples: How do system reliability levels affect the QoS levels of the service providers and brokers under competition? How do system reliability levels affect the profits of resource providers and brokers in a competitive market? How do system reliability levels influence the pricing of the services in a competitive environment? How do users' service request types, QoS requirements, and timing concerns affect users' behaviors, costs and risks in equilibrium? How does the market mechanism allocate resources to satisfy the demands of users? We find that for users who request same services certain timing flexibility can not only reduce the costs but also lower the risks. The results indicated that the value of QoS can be efficiently priced based on the heterogeneous service demands.     

On total stability of competitive equilibrium

Despite the fact that the demand and supply characteristics of n competitive market are inherently non-stationary, stability properties of time-varying models of multiple markets have remained largely unexplored. The purpose of this work is to introduce a time-dependent non-linear formulation of the excess demand function, and consider time-varying effects on stability of the competitive equilibrium caused by structural changes in the interactions among individual markets. It will be shown that the classical Hicks conditions are sufficient (and sometimes necessary) for stability of a large class of non-linear non-stationary models of multiple market systems.     

Auction-based distributed efficient economic operations of microgrid systems

This paper studies the economic operations of the microgrid in a distributed way such that the operational schedule of each of the units, like generators, load units, storage units, etc., in a microgrid system, is implemented by autonomous agents. We apply and generalise the progressive second price (PSP) auction mechanism which was proposed by Lazar and Semret to efficiently allocate the divisible network resources. Considering the economic operation for the microgrid systems, the generators play as sellers to supply energy and the load units play as the buyers to consume energy, while a storage unit, like battery, super capacitor, etc., may transit between buyer and seller, such that it is a buyer when it charges and becomes a seller when it discharges. Furthermore in a connected mode, each individual unit competes against not only the other individual units in the microgrid but also the exogenous main grid possessing fixed electricity price and infinite trade capacity; that is to say, the auctioneer assigns the electricity among all individual units and the main grid with respect to the submitted bid strategies of all individual units in the microgrid in an economic way. Due to these distinct characteristics, the underlying auction games are distinct from those studied in the literature. We show that under mild conditions, the efficient economic operation strategy is a Nash equilibrium (NE) for the PSP auction games, and propose a distributed algorithm under which the system can converge to an NE. We also show that the performance of worst NE can be bounded with respect to the system parameters, say the energy trading price with the main grid, and based upon that, the implemented NE is unique and efficient under some conditions.     

Concurrent engineering: The manufacturing philosophy for the 90''s

Concurrent Engineering (CE) has recently been recognized as a more integrated approach to develope high quality products and bringing them to highly competitive global market at lower price and in significantly less time. In the past few years, an increasing effort has been made to understand and implement the principles of CE. However, there has been insufficient attempt to document these principles systematically. This paper examines the subject of CE and the ongoing studies which emphasize its various functions. A summary is presented and the projection of possible future research is discussed.     

Harnessing information for development: A proposal for a world bank group vision and strategy∗

Abstract

Revolutionary advances in information technology reinforce economic and social changes that are transforming business and society. A new kind of economy ‐ the information economy ‐ is emerging where trade and investment are global and firms compete with knowledge, networking and agility on a global basis. A corresponding new society is also emerging with pervasive information capabilities that make it substantially different from an industrial society: more competitive, more democratic, less centralized, less stable, better able to address individual needs, and friendlier to the environment.

These changes dictate, for all countries, a major adjustment to harness information for economic and social development. This adjustment requires urgent new policies, regulatory and institutional reforms, and investments. Through this adjustment, countries must achieve macroeconomic balance, political stability, and growth amidst global information flows, competition, trade, and investment. Advanced countries are rapidly adjusting. Developing countries must also adjust or risk exclusion from the global economy and severe competitive disadvantage for their goods and services.

Fortunately, the information revolution creates both the challenge and the means for countries to adjust to new ways of doing business and to put in place the needed infrastructure of telecommunications and information systems. The information revolution also creates extraordinary new opportunities to attack vexing problems of poverty, inequality, and environmental degradation.

To harness information and information technology for its mission of poverty alleviation and sustainable economic development, the World Bank Group will pursue four objectives in its assistance strategy:

• Widespread and equitable access to communication and information services through accelerated deployment of national information infrastructure and effective integration into international communication and information networks.

• Systemic improvements in the functioning and competitiveness of key economic sectors through strategic information policies and systems.

• New ways to use information technology to help solve the most pressing problems of human and economic development ‐ education, health, poverty alleviation, rural development, and care for the environment.

• Increased impact of the entire range of World Bank Group operations through inclusion of effective information components.

The World Bank Group will be a long‐term partner and facilitator for countries adjusting to the information economy. It will cooperate with them on information policy, strategy, and project design at the national and sectoral levels. To this end, it will develop strategic alliances to mobilize worldwide knowledge and financing, including its own. In addition, the World Bank Group will increase the level and effectiveness of the information content of its projects in all sectors and will explore new frontiers of development through information‐intensive projects.     

The effects of market power on the stocks and prices of world coffee

The objective of this study is to explore the consequences of market power for optimal stockholding and price variations in the world coffee economy. Optimal storage decision rules which incorporate risk aversion under several market scenarios are considered. These generate a set of price and quantity series that can be compared with the historical data and to test the hypothesis proposed by Newbery that a monopolistic producer tends to undertake more storage than a competitive producer and hence price stability may increase in proportion to the dominant role played by the monopolist. Our study reveals that the world coffee market has been rather close to the competitive regime since the 1960s. As far as price variations are concerned, results are not always consistent with the Newbery hypothesis.     

Oligopolistic spectrum allocation game via market competition under spectrum broker

For future dynamic spectrum access (DSA) systems, new spectrum management methodologies will be adopted such that the licensed primary spectrum holders can reallocate part of their available bandwidth to the unlicensed secondary service providers for profits, based on market-driven mechanisms. This is known as spectrum market or spectrum trading. This paper aims to propose a dynamic spectrum market model where each spectrum holder has a limited amount of spectrum and is allowed to enter a portion of its available bandwidth into the market managed by a spectrum broker, besides its primary services. To model the price dynamics, a continuous-time price adjustment process governed by a differential equation is considered. Subsequently, we show that the problem is a dynamic N-player oligopoly differential game, subject to the bandwidth constraint. We analyze the feedback Nash equilibrium (NE) solutions for the general game and provide a complete, closed-form solution for the special symmetric case. The solution can be characterized into three distinct regions and transitions between these regions may occur as time evolves, which will be thoroughly investigated. In addition, we propose a discrete-time price adjustment implemented at the spectrum broker. Extensive numerical studies are provided to investigate various aspects of the proposed competition.     

Multimedia polysensory integration training system dedicated to children with educational difficulties

Ranking of search results and ads has traditionally been studied separately. The probability ranking principle is commonly used to rank the search results while the ranking based on expected profits is commonly used for paid placement of ads. These rankings try to maximize the expected utilities based on the user click models. Recent empirical analysis on search engine logs suggests unified click models for both ranked ads and search results (documents). These new models consider parameters of (i) probability of the user abandoning browsing results (ii) perceived relevance of result snippets. However, current document and ad ranking methods do not consider these parameters. In this paper we propose a generalized ranking function—namely Click Efficiency (CE)—for documents and ads based on empirically proven user click models. The ranking considers parameters (i) and (ii) above, optimal and has the same time complexity as sorting. Furthermore, the CE ranking exploits the commonality of click models, hence is applicable for both documents and ads. We examine the reduced forms of CE ranking based upon different underlying assumptions, enumerating a hierarchy of ranking functions. Interestingly, some of the rankings in the hierarchy are currently used ad and document ranking functions; while others suggest new rankings. Thus, this hierarchy illustrates the relationships between different rankings, and clarifies the underlying assumptions. While optimality of ranking is sufficient for document ranking, applying CE ranking to ad auctions requires an appropriate pricing mechanism. We incorporate a second price based mechanism with the proposed ranking. Our analysis proves several desirable properties including revenue dominance over Vickrey Clarke Groves (VCG) for the same bid vector and existence of a Nash equilibrium in pure strategies. The equilibrium is socially optimal, and revenue equivalent to the truthful VCG equilibrium. As a result of its generality, the auction mechanism and the equilibrium reduces to the current mechanisms including Generalized Second Price Auction (GSP) and corresponding equilibria. Furthermore, we relax the independence assumption in CE ranking and analyze the diversity ranking problem. We show that optimal diversity ranking is NP-Hard in general, and a constant time approximation algorithm is not likely. Finally our simulations to quantify the amount of increase in different utility functions conform to the results, and suggest potentially significant increase in utilities.     

基于分数阶导数的经济波动模型的稳定性研究

分析了含有分数阶导数的经济波动模型,其中分数阶导数描述了经济变量的长记忆性质.将随机动力系统的概念引入到了经济波动模型以理解经济波动的本质特征.主要研究了经济波动问题中的平衡状态的稳定性以及经济波动的波动幅度问题.首先,我们研究了经济变量的记忆性质对经济波动的稳定性和波动幅度的影响.结果表明,经济变量的长记忆性延长了经济系统到达平衡状态的时间,这对宏观经济调控提供了一个新的视角和观点.其次,我们研究了分数阶导数如何影响和改变经济波动的波动幅度.结果显示相比于经典模型,经济变量的时间记忆特性会产生不同的令人惊奇的现象.     

Dynamic Balance Control Based on an Adaptive Gain-scheduled Backstepping Scheme for Power-line Inspection Robots

This paper presents an adaptive gain-scheduled backstepping control (AGSBC) scheme for the balance control of an underactuated mechanical power-line inspection (PLI) robotic system with two degrees of freedom and a single control input. First, a nonlinear dynamic model of the balance adjustment process of the PLI robot is constructed, and then the model is linearized at a nominal equilibrium point to overcome the computational infeasibility of the conventional backstepping technique. Second, to solve generalized stabilization control issue for underactuated systems with multiple equilibrium points, an equilibrium manifold linearized model is developed using a scheduling variable, and then a gain-scheduled backstepping control (GSBC) scheme for expanding the operational area of the controlled system is constructed. Finally, an adaptive mechanism is proposed to counteract the impact of external disturbances. The robust stability of the closed-loop system is ensured by Lyapunov theorem. Simulation results demonstrate the effectiveness and high performance of the proposed scheme compared with other control schemes.      

Coordination mechanisms

We introduce the notion of coordination mechanisms to improve the performance in systems with independent selfish and non-colluding agents. The quality of a coordination mechanism is measured by its price of anarchy—the worst-case performance of a Nash equilibrium over the (centrally controlled) social optimum. We give upper and lower bounds for the price of anarchy for selfish task allocation and congestion games.