Sharmila Savarimuthu

Mechanisms for Cooperative Behaviour in Agent Institutions

Our approach is described for maintaining sustainable cooperative behaviour in agent-based peer-to-peer systems whose environments are organized into agent institutional societies. Instead of expelling uncooperative society members, our approach considers institutional mechanisms that attempt to encourage cooperative behaviour among society members in order to maintain satisfactory operational performance of the institution. This is accomplished by- dividing the society into subgroups, each of which is managed by a special monitor agent. The subgroup monitor agents help keep track of member agent reputations and manage the associated tags for each of the agents in their subgroup. Some experimental results are presented describing how these mechanisms operate.

Gossip-Based Self-Organising Agent Societies and the Impact of False Gossip

The objective of this work is to demonstrate how cooperative sharers and uncooperative free riders can be placed in different groups of an electronic society in a decentralised manner. We have simulated an agent-based open and decentralised P2P system which self-organises itself into different groups to avoid cooperative sharers being exploited by uncooperative free riders. This approach encourages sharers to move to better groups and restricts free riders into those groups of sharers without needing centralised control. Our approach is suitable for current P2P systems that are open and distributed. Gossip is used as a social mechanism for information sharing which facilitates the formation of groups. Using multi-agent based simulations we demonstrate how the adaptive behaviour of agents lead to self-organisation. We have tested with varying the gossip level and checked its impact in the system’s behaviour. We have also investigated the impact of false gossip in this system where gossip is the medium for information sharing which leads to self-organisation.

Mechanisms for the self-organization of peer groups in agent societies

New mechanisms for group self-organization in agent societies are investigated and examined in the context of sharing digital goods. Specifically we illustrate how cooperative sharers and uncooperative free riders can be placed in different groups of an electronic society in a decentralized manner. We have simulated a decentralized, open P2P system which self-organizes itself to avoid cooperative sharers being exploited by uncooperative free riders. Inspired by human society, we use social mechanisms such as tags, gossip and ostracism. This approach encourages sharers to move to better groups and restricts free riders without necessitating centralized control, which makes the system appropriate for current open P2P systems.

Emergence of Sharing Behavior in a Multi-agent Society Using Tags

This paper investigates how tags can be used to achieve emergence of sharing behavior in a multi-agent society made of different groups. The context of interaction between agents in the society is the knowledge-sharing game, where agents use tags to identify those who are similar to them. This paper explains under what circumstances tags succeed to establish knowledge sharing. The results discussed in this paper were obtained using the simulation of artificial agent societies.

Self-Organization of Peers in Agent Societies

This paper investigates how tags can be used to achieve self-organization of groups in a multi agent society where nodes of a P2P system are modeled as simple interacting agents located in different groups. The context of interaction between agents is the sharing of digital goods in electronic societies. This paper explains how cooperative sharers and uncooperative free riders can be placed in different groups of a P2P system in a decentralized manner. We have simulated a decentralized, distributed, P2P system which self-organizes itself to avoid cooperative sharers being exploited by uncooperative free riders. The developed system based on a gossip mechanism shows promising results by encouraging sharers to move to better groups and also by restricting free riders without any centralized control, which makes it favorable for current P2P systems. The results discussed in this paper were obtained using the simulation of artificial agent societies.

Altruistic sharing using tags

This paper discusses altruistic sharing achieved by tags in an agent society where sharing information incurs a cost and non-sharing is thus the preferred option for selfish agents. We believe that the general features of our tagging mechanism can be used to facilitate altruism and increase the overall social welfare in artificial societies. We describe our findings based on experiments we have conducted through multi-agent-based simulation of artificial societies in the context of agents playing the knowledge-sharing game.

Emergence of a Sharing Norm in a Simulated Hunter-Gatherer Society

Sharing is a behaviour that is observed in humans and other primates. In this paper, our objective is to demonstrate how the norm of sharing changes based on environmental conditions. Using agent based modeling, we have simulated a hunter-gatherer society where the norms of the society are affected by changing environmental conditions. In particular, we demonstrate how norms might change in a society based on the changes to type of resources available in the society. We present several experiments that have been conducted on the emergence of the sharing norm and discuss the results obtained.

Gossip-Based self-organising open agent societies

The objective of this work is to demonstrate how cooperative sharers and uncooperative free riders can be placed in different groups of an electronic society in a decentralized manner. We have simulated an agent-based open and decentralized P2P system which self-organises itself into different groups to avoid cooperative sharers being exploited by uncooperative free riders. This approach encourages sharers to move to better groups and restricts free riders into those groups of sharers without needing centralized control. Our approach is suitable for current P2P systems that are open and distributed. Gossip is used as a social mechanism for information sharing which facilitates the formation of groups. Using multi-agent based simulations we demonstrate how the adaptive behaviour of agents lead to self-organization.

An agent-based simulation for restricting exploitation in electronic societies through social mechanisms

AbstractOne of the problems in artificial agent societies is the problem of non-cooperation, where individuals have motivations for not cooperating with others. An example of non-cooperation is the issue of freeriding, where some agents do not contribute to the welfare of the society but do consume valuable resources. New mechanisms for group self-organisation and management in multi-agent societies are presented and examined in a multi-agent societies where nodes of a P2P system are modelled as interacting agents belonging to different groups. The context of interaction between agents is the sharing of digital goods in electronic societies. We have simulated a decentralised P2P system which self-organises itself to avoid cooperative sharers being exploited by uncooperative free riders. Specifically, we illustrate how cooperative sharers and uncooperative free riders can be placed in different groups of an electronic society in a decentralised manner. Inspired by human society, we use social mechanisms such as tags, gossip and ostracism. Our aim here is to restrict exploitation or in other words restrict uncooperative behaviour by separating groups based on performance since it reduces the likelihood of bad agents exploiting the good agents in the better groups. The developed system shows promising results by encouraging sharers to move to better groups and also by restricting free riders without any centralised control, which makes these mechanisms appropriate for distributed policy governance. Our work offers new insights into policy mechanisms for regulation of distributed societies.