Developing agent Web service agreements

Web services have emerged as a new paradigm that supports loosely-coupled distributed systems in service discovery and service execution. Next generation Web services evolve from performing static invocations to engaging in flexible interactions and negotiations for dynamic resource procurement. To this end, this paper applies an agent-oriented based approach over a Web service language, WS-Agreement, in order to facilitate conversations of sufficient expressiveness between adaptive and autonomous services. We discuss how such agent Web service agreements can be implemented over IBM's emerging technologies toolkit (ETTK) that itself includes an implementation of the WS-Agreement specification

A comparative study of game theoretic and evolutionary models for software agents

Most of the existing work in the study of bargaining behaviour uses techniques from game theory. Game theoretic models for bargaining assume that players are perfectly rational and that this rationality in common knowledge. However, the perfect rationality assumption does not hold for real-life bargaining scenarios with humans as players, since results from experimental economics show that humans find their way to the best strategy through trial and error, and not typically by means of rational deliberation. Such players are said to be boundedly rational. In playing a game against an opponent with bounded rationality, the most effective strategy of a player is not the equilibrium strategy but the one that is the best reply to the opponent's strategy. The evolutionary model provides a means for studying the bargaining behaviour of boundedly rational players. This paper provides a comprehensive comparison of the game theoretic and evolutionary approaches to bargaining by examining their assumptions, goals, and limitations. We then study the implications of these differences from the perspective of the software agent developer

A Parameterisation of Algorithms for Distributed Constraint Optimisation via Potential Games

This paper introduces a parameterisation of learning algorithms for distributed constraint optimisation problems (DCOPs). This parameterisation encompasses many algorithms developed in both the computer science and game theory literatures. It is built on our insight that when formulated as noncooperative games, DCOPs form a subset of the class of potential games. This result allows us to prove convergence properties of algorithms developed in the computer science literature using game theoretic methods. Furthermore, our parameterisation can assist system designers by making the pros and cons of, and the synergies between, the various DCOP algorithm components clear

Taxation and stability in cooperative games

Cooperative games are a useful framework for modeling multi-agent behavior in environments where agents must collaborate in order to complete tasks. Having jointly completed a task and generated revenue, agents need to agree on some reasonable method of sharing their profits. One particularly appealing family of payoff divisions is the core, which consists of all coalitionally rational (or, stable) payoff divisions. Unfortunately, it is often the case that the core of a game is empty, i.e. there is no payoff scheme guaranteeing each group of agents a total payoff higher than what they can get on their own. As stability is a highly attractive property, there have been various methods of achieving it proposed in the literature. One natural way of stabilizing a game is via taxation, i.e. reducing the value of some coalitions in order to decrease their bargaining power. Existing taxation methods include the ε-core, the least-core and several others. However, taxing coalitions is in general undesirable: one would not wish to overly tamper with a given coalitional game, or overly tax the agents. Thus, in this work we study minimal taxation policies, i.e. those minimizing the amount of tax required in order to stabilize a given game. We show that games that minimize the total tax are to some extent a linear approximation of the original games, and explore their properties. We demonstrate connections between the minimal tax and the cost of stability, and characterize the types of games for which it is possible to obtain a tax-minimizing policy using variants of notion of the ε-core, as well as those for which it is possible to do so using reliability extensions. Copyright © 2013, International Foundation for Autonomous Agents and Multiagent Systems (www.ifaamas.org). All rights reserved

Matchings with externalities and attitudes

Two-sided matchings are an important theoretical tool used to model markets and social interactions. In many real-life problems the utility of an agent is influenced not only by their own choices, but also by the choices that other agents make. Such an influence is called an externality. Whereas fully expressive representations of externalities in matchings require exponential space, in this paper we propose a compact model of externalities, in which the influence of a match on each agent is computed additively. Under this framework, we analyze many-to-many matchings and one-to-one matchings where agents take different attitudes when reasoning about the actions of others. In particular, we study optimistic, neutral and pessimistic attitudes and provide both computational hardness results and polynomial-time algorithms for computing stable outcomes

Formal Specification of Multi-Agent Systems: a Real World Case

In this paper the framework DESIRE, originally designed for formal specification of complex reasoning systems is used to specify a real-world multi-agent application on a conceptual level. Some extensions to DESIRE are introduced to obtain a useful formal specification framework for multi-agent systems

Современные технические средства в работе секретаря

The article examines the technical devices used in the secretary work. Guided books and magazines for secretarial business, makes recommendations for the proper selection and use of technical devices. Furthermore, in this article the author gives examples of the most popular and commonly used programs for personal computers. All of these techniques can significantly reduce the cost of working time and improve the quality of performing their job duties

Expectation-Oriented Analysis and Design

A key challenge for agent-oriented software engineering is to develop and implement open systems composed of interacting autonomous agents. On the one hand, there is a need for permitting autonomy in order to support desirable system properties such as decentralised control. On the other hand, there is a need for restricting autonomy in order to reduce undesirable system properties such as unpredictability. This paper introduces a novel analysis and design method for open agent-oriented software systems that aims at coming up to both of these two contrary aspects. The characteristics of this method, called EXPAND, are as follows: (i) it allows agents a maximum degree of autonomy and restricts autonomous behaviour only if necessary (ii) it uses systemlevel expectations as a key modelling abstraction and as the primary level of analysis and design; and (iii) it is sociologically grounded in Luhmann's systems theory. The application of EXPAND is illustrated in a "car-trading platform" case study