Chris Preist

Adaptive agents in a persistent shout double auction

agents, double auction, electronic trading, negotiation, adaptive behaviour Cliff (1997) has demonstrated that simple, adaptive agents are able to trade in a form of double auction marketplace, in such a way that trade prices converge towards the equilibrium price of the marketplace. However, the marketplace within which the agents trade is unrealistic. In this paper, we consider a more realistic form of double auction market, the persistent shout double auction. We present agents based on the ZIP agents of Cliff (1997), but with an alternative set of heuristics for use within this auction. We demonstrate that the resulting agents achieve equilibrium significantly faster than ZIP agents do, maintain a more stable equilibrium, and are more robust to changes in learning rate.

A Manifesto for Agent Technology: Towards Next Generation Computing

The European Commissions eEurope initiative aims to bring every citizen, home, school, business and administration online to create a digitally literate Europe. The value lies not in the objective itself, but in its ability to facilitate the advance of Europe into new ways of living and working. Just as in the first literacy revolution, our lives will change in ways never imagined. The vision of eEurope is underpinned by a technological infrastructure that is now taken for granted. Yet it provides us with the ability to pioneer radical new ways of doing business, of undertaking science, and, of managing our everyday activities. Key to this step change is the development of appropriate mechanisms to automate and improve existing tasks, to anticipate desired actions on our behalf (as human users) and to undertake them, while at the same time enabling us to stay involved and retain as much control as required. For many, these mechanisms are now being realised by agent technologies, which are already providing dramatic and sustained benefits in several business and industry domains, including B2B exchanges, supply chain management, car manufacturing, and so on. While there are many real successes of agent technologies to report, there is still much to be done in research and development for the full benefits to be achieved. This is especially true in the context of environments of pervasive computing devices that are envisaged in coming years. This paper describes the current state-of-the-art of agent technologies and identifies trends and challenges that will need to be addressed over the next 10 years to progress the field and realise the benefits. It offers a roadmap that is the result of discussions among participants from over 150 organisations including universities, research institutions, large multinational corporations and smaller IT start-up companies. The roadmap identifies successes and challenges, and points to future possibilities and demands; agent technologies are fundamental to the realisation of next generation computing.

A conceptual architecture for semantic web services

In this paper, we present an abstract conceptual architecture for semantic web services. We define requirements on the architecture by analyzing a set of case studies developed as part of the EU Semantic Web-enabled Web Services project. The architecture is developed as a refinement and extension of the W3C Web Services Architecture. We assess our architecture against the requirements, and provide an analysis of OWL-S.

A software framework for automated negotiation

If agents are to negotiate automatically with one another they must share a negotiation mechanism, specifying what possible actions each party can take at any given time, when negotiation terminates, and what is the structure of the resulting agreements. Current standardization activities such as FIPA [2] and WS-Agreement [3] represent this as a negotiation protocol specifying the flow of messages. However, they omit other aspects of the rules of negotiation (such as obliging a participant to improve on a previous offer), requiring these to be represented implicitly in an agent’s design, potentially resulting incompatibility, maintenance and re-usability problems. In this chapter, we propose an alternative approach, allowing all of a mechanism to be formal and explicit. We present (i) a taxonomy of declarative rules which can be used to capture a wide variety of negotiation mechanisms in a principled and well-structured way; (ii) a simple interaction protocol, which is able to support any mechanism which can be captured using the declarative rules; (iii) a software framework for negotiation that allows agents to effectively participate in negotiations defined using our rule taxonomy and protocol and (iv) a language for expressing aspects of the negotiation based on OWL-Lite [4]. We provide examples of some of the mechanisms that the framework can support.

Semantic web support for the business-to-business e-commerce lifecycle

If an e-services approach to electronic commerce is to become widespread, standardisation of ontologies, message content and message protocols will be necessary. In this paper, we present a lifecycle of a business-to-business e-commerce interaction, and show how the Semantic Web can support a service description language that can be used throughout this lifecycle. By using DAML, we develop a service description language sufficiently expressive and flexible to be used not only in advertisements, but also in matchmaking queries, negotiation proposals and agreements. We also identify which operations must be carried out on this description language if the B2B lifecycle is to be fully supported. We do not propose specific standard protocols, but instead argue that our operators are able to support a wide variety of interaction protocols, and so will be fundamental irrespective of which protocols are finally adopted.

Negotiation in multi-agent systems

In systems composed of multiple autonomous agents, negotiation is a key form of interaction that enables groups of agents to arrive at a mutual agreement regarding some belief, goal or plan, for example. Particularly because the agents are autonomous and cannot be assumed to be benevolent, agents must influence others to convince them to act in certain ways, and negotiation is thus critical for managing such inter-agent dependencies. The process of negotiation may be of many different forms, such as auctions, protocols in the style of the contract net, and argumentation, but it is unclear just how sophisticated the agents or the protocols for interaction must be for successful negotiation in different contexts. All these issues were raised in the panel session on negotiation.

Decision procedures for multiple auctions

This paper presents a decision theoretic framework that an autonomous agent can use to bid effectively across multiple, simultaneous auctions. Specifically, our framework enables an agent to make rational decisions about purchasing multiple goods from a series of auctions that operate different protocols (we deal with the English, Dutch, First-Price Sealed Bid and Vickrey cases). The framework is then used to characterize the optimal decision that an agent should take. Finally, we develop a practical algorithm that provides a heuristic approximation to this ideal.

Architecting for reuse: a software framework for automated negotiation

If agents are to negotiate automatically with one another they must share a negotiation mechanism, specifying what possible actions each party can take at any given time, when negotiation terminates, and what the resulting agreements will be. The current state-of-the-art represents this as a negotiation protocol specifying the flow of messages. However, they omit other aspects of the rules of negotiation (such as obliging a participant to improve on a previous offer), requiring these to be represented implicitly in an agents design, potentially resulting in compatibility, maintenance and re-usability problems. In this paper, we propose an alternative approach, allowing all of a mechanism to be formal and explicit. We present (i) A taxonomy of declarative rules which can be used to capture a wide variety of negotiation mechanisms in a principled and well-structured way. (ii) A simple interaction protocol, which is able to support any mechanism which can be captured using the declarative rules. (iii) A software framework for negotiation, implemented in JADE [3] that allows agents to effectively participate in negotiations defined using our rule taxonomy and protocol.

Automated Trading in Agent-Based Markets for Communication Bandwidth

Automated agentsfor electronic markets are very valuable when a large amount of information must be processed quickly or employing human traders is not cost-effective. In markets for communication bandwidth, rights to transmit data are traded through a network. Since demand fluctuates considerably every few seconds, agent-based spot markets provide extra liquidity.This paper considers the design of agents for use in a double auction market for communication bandwidth. The suggested criteria and framework for building adaptive agents are based on statistical decision theory.The proposed agents can differentiate stable from unstable market conditions and respond appropriately.

Economic dynamics of agents in multiple auctions

Over the last few years, electronic auctions have become an increasingly important aspect of e- commerce, both in the business to business and business to consumer domains. As a result of this, it is often possible to find many auctions selling similar goods on the web. However, when an individual is attempting to purchase such a good, they will usually bid in one, or a small number, of such auctions. This results in two forms of inefficiency. Firstly, the individual may pay more for the good than would be expected in an ideal market. Secondly, some sellers may fail to make a sale that could take place in an ideal market. In this paper, we present an agent that is able to participate in multiple auctions for a given good, placing bids appropriately to secure the cheapest price. We present experiments to show; (i) Current auction markets on the web are inefficient, with trades taking place away from equilibrium price, and not all benefit from trade being extracted. (ii) Our agent is able to exploit these inefficiencies, resulting in it making higher profits than the simple strategy of bidding in a small number of auctions. (iii) As more participants use our agent, the market becomes more efficient. When all participants use the agent, all trades take place close to equilibrium price, and the market approaches ideal behaviour.