Escaping Local Optima in Multi-Agent Oriented Constraint Satisfaction

  • Muhammed Basharu
  • Hatem Ahriz
  • Inés Arana
Conference paper


We present a multi-agent approach to constraint satisfaction where feedback and reinforcement are used in order to avoid local optima and, consequently, to improve the overall solution. Our approach, FeReRA, is based on the fact that an agent’s local best performance does not necessarily contribute to the system’s best performance. Thus, agents may be rewarded for improving the system’s performance and penalised for not contributing towards a better solution. Hence, agents may be forced to choose sub-optimal moves when they reach a specified penalty threshold as a consequence of their lack of contribution towards a better overall solution. This may allow other agents to choose better moves and, therefore, to improve the overall performance of the system. FeReRA is tested against its predecessor, ERA, and a comparative evaluation of both approaches is presented.


Local Optimum Problem Instance Constraint Satisfaction Constraint Satisfaction Problem Graph Colouring Problem 
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Copyright information

© Springer-Verlag London 2004

Authors and Affiliations

  • Muhammed Basharu
    • 1
  • Hatem Ahriz
    • 1
  • Inés Arana
    • 1
  1. 1.School of ComputingThe Robert Gordon UniversityAberdeenUK

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