Bastin Tony Roy Savarimuthu

Norm creation, spreading and emergence: A survey of simulation models of norms in multi-agent systems

Norms in human societies are expectations of behaviours of the individuals. In human societies, there are several types of norms such as moral norms, social norms and legal norms (laws). In multi-agent systems, software agents are modelled as possessing characteristics and behaviour borrowed from human societies. In order to design and develop robust artificial agent societies, it is important to understand different approaches proposed by researchers by which norms can spread and emerge within agent societies. This paper makes three contributions to the study of norms. Firstly, based on the simulation research on norms, we propose a life-cycle model for norms. Secondly, we discuss different mechanisms used by researchers to study norm creation, identification, spreading, enforcement and emergence. We also discuss the strengths and weaknesses of each of these mechanisms. Thirdly, in the context of identifying the desired characteristics of the simulation models of norms we discuss the research issues that need to be addressed.

Role model based mechanism for norm emergence in artificial agent societies

In this paper we propose a mechanism for norm emergence based on role models. The mechanism uses the concept of normative advice whereby the role models provide advice to the follower agents. Our mechanism is built using two layers of networks, the social link layer and the leadership layer. The social link network represents how agents are connected to each other. The leadership network represents the network that is formed based on the role played by each agent on the social link network. The two kinds of roles are leaders and followers. We present our findings on how norms emerge on the leadership network when the topology of the social link network changes. The three kinds of social link networks that we have experimented with are fully connected networks, random networks and scale-free networks.

Social norm emergence in virtual agent societies

The advent of virtual environments such as SecondLife call for a distributed approach for norm emergence and spreading. In open virtual environments, monitoring various interacting agents (avatars), using a centralized authority might be computationally expensive. The number of possible states and actions of an agent could be huge. An approach for sustaining order and smoother functioning of these environments can be facilitated through norms. Agents can generate norms based on interactions. In particular, those social norms that incur certain cost to an individual agent but benefit the whole society are more interesting than those benefit both the agent and the society. The problem is that the selfish agents might not be willing to share the norm adherence cost. In this work, we experiment with notion proposed by Axelrod that social norms are best at preventing small defections where the cost of enforcement is low. We also study how common knowledge can be used to faciliate the overall benefit of the society. We believe our work can be used to facilitate norm emergence in virtual online societies.

Agent-based workflow management systems (WfMSs)

Workflow management systems (WfMSs) based on agent technology can cope with the rapidly evolving business environment better than most other systems as they are more flexible and open. In this paper we describe a possible architecture of such a system by means of our prototype WfMS called JBees. The combination of collaborating agents and the Coloured Petri Net (CPN)-formalism in JBees enables a flexible and adaptive system with the possibility of simulation, analysis, and monitoring of the process execution in order to identify potential inconsistencies and to provide appropriate information to the workflow administrator for the purpose of the process improvement.

Norm emergence in agent societies formed by dynamically changing networks

In this paper we describe how our previously proposed role model agent mechanism for norm emergence can be applied to artificial agent societies with network topologies that are changing dynamically. Dynamically changing network topologies account for agents joining and leaving the network and the links that are created and removed between agents in a society. In order to construct a dynamically changing network we have adopted a model representing agents as particles colliding in a social space. We demonstrate that the role model agent mechanism for norm emergence works on top of dynamically created network topologies that represent social relationship structures.

Agent-based integration of Web Services with Workflow Management Systems

Rapid changes in the business environment call for more flexible and adaptive workflow systems. Researchers have proposed that Workflow Management Systems (WfMSs) comprising multiple agents can provide these capabilities. We have developed a multiagent based workflow system, JBees, which supports distributed process models and the adaptability of executing processes. Modern workflow systems should also have the flexibility to integrate available Web Services as they are updated. In this paper we discuss how our agent-based architecture can be used to bind and access Web Services in the context of executing a workflow process model.

Integrating Web Services with Agent Based Workflow Management System (WfMS)

Rapid changes in the business environment call for more flexible and adaptive workflow systems. Researchers have proposed that workflow management systems (WfMSs) comprising multiple agents can provide these capabilities. We have developed a multi-agent based workflow system, JBees, which supports distributed process models and the adaptability of executing processes. Modern workflow systems should also have the flexibility to integrate available Web services as they are updated. In this paper, we discuss how our agent-based architecture can be used to bind and access Web services in the context of executing a workflow process model. We use an example from the diamond processing industry to show how our agent architecture can be used to integrate Web services with WfMSs.

Identifying prohibition norms in agent societies

In normative multi-agent systems, the question of “how an agent identifies norms in an open agent society” has not received much attention. This paper aims at addressing this question. To this end, this paper proposes an architecture for norm identification for an agent. The architecture is based on observation of interactions between agents. This architecture enables an autonomous agent to identify prohibition norms in a society using the prohibition norm identification (PNI) algorithm. The PNI algorithm uses association rule mining, a data mining approach to identify sequences of events as candidate norms. When a norm changes, an agent using our architecture will be able to modify the norm and also remove a norm if it does not hold in the society. Using simulations of a park scenario we demonstrate how an agent makes use of the norm identification framework to identify prohibition norms.

PRIMA 2013: Principles and Practice of Multi-Agent Systems

This book constitutes the refereed proceedings of the 16th International Conference on Principles and Practice of Multi-Agent Systems, PRIMA 2013, held in Dunedin, New Zealand, in December 2013. The conference was co-located with the 26th Australasian Artificial International Conference, AI 2013. The 24 revised full papers presented together with 18 short papers and 2 invited papers were carefully reviewed and selected from 81 submissions. The papers are organized in topical sections on foundations of agents and multi-agent systems; agent and multi-agent system architectures; agent-oriented software engineering; agent-based modelling and simulation; cooperation/collaboration, coordination/communication; hybrid technologies, application domains; and applications.

Aspects of active norm learning and the effect of lying on norm emergence in agent societies

Norms have facilitated smoother functioning in human societies. In the field of normative multi-agent systems researchers are interested in investigating how the concept of social norms can be used to facilitate social order in electronic agent societies. In this context, the area of norm emergence has attracted a lot of interest among researchers. The objectives of this paper are two-fold. First, we discuss the norm learning approaches in agent societies and discuss the three aspects of active norm learning (experiential, observational and communication-based learning) in agent societies. Using an example we demonstrate the usefulness of combining these three aspects of norms learning. Second, we investigate the effect of the presence of liars in an agent society on norm emergence. Agents that lie distort truth when they are asked about the norm in an agent society. We show that lying has deleterious effect on norm emergence. In particular, using simulations we identify conditions under which the norms that have emerged in a society can be sustained in the presence of liars.