Session:

Multi-Agent Systems
Tuesday, March 02, 2004, 12.30 – 12.50

Session Chair:

Gulnara Baldoquín de la Peña

Paper Title:

Enhancing the Effectiveness of Simple Multi-Agent Systems Through Stigmergic Coordination

Author(s):

S. Negulescu, "Lucian Blaga" University of Sibiu, Romania
B. E. Barbat, "Lucian Blaga" University of Sibiu, Romania

Abstract:

After detailing the terminology employed, the paper explains the rationale of choosing stigmergic coordination to enhance the problem-solving power of simple MAS, emphasizing the engineering advantages (very simple entities, unaware of each other). To be affordable on usual configurations, a reduced number of agents and a problem-class of manageable complexity are needed. To be comparable against related work, an effectiveness measure is defined and two reference usual algorithms are chosen. All tests apply to the Travelling Salesperson Problem (TSP) solved with variants of the Elitist Ant System (EAS). The paper follows two paths: searching for local enhancements (based on the biological model) and creating a problem-solving method for TSP (searching for inter-paradigmatic synergy). The first path proved useful (from about 45 algorithm instances tested out, 22 gave relevant results): effectiveness is visible (albeit not much) enhanced by fine-tuning the EAS. The second (more promising) path is based on adding symbolic processing factors (adapting the environment and instituting a limited central coordination). Since now the added factors are controlled externally, quantitative evaluations are missing but improvements are apparent. The paper concludes that stigmergic coordination improves effectiveness on affordable configurations with simple MAS, classical problems and usual benchmarks.