On the Utility of Redundant Encodings in Mutation-Based Evolutionary Search

  • Joshua D. Knowles
  • Richard A. Watson
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 2439)


A number of recent works in the evolutionary computation field have suggested that introducing large amounts of genetic redundancy may increase the evolvability of a population in an evolutionary algorithm. These works have variously claimed that the reliability of the search, the final fitness achieved, the ability to cope with changing environments, and the robustness to high mutation rates, may all be improved by employing this strategy. In this paper we dispute some of these claims, arguing that adding random redundancy cannot be generally useful for optimization purposes. By way of example we report on experiments where a proposed neutral encoding scheme (based on random Boolean networks) is compared to a direct encoding in two mutation-only EAs, at various mutation rates. Our findings show that with the appropriate choice of per-bit mutation rate, the evolvability of populations using the direct encoding is no less than with the redundant one.


Mutation Rate Binary String High Mutation Rate Neutral Network Adaptive Landscape 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2002

Authors and Affiliations

  • Joshua D. Knowles
    • 1
  • Richard A. Watson
    • 2
  1. 1.IRIDIA— CP 194/6Université Libre de BruxellesBrusselsBelgium
  2. 2.DEMO, Volen Center for Complex SystemsBrandeis UniversityWalthamUSA

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