Ignoble Trails - Where Crossover Is Provably Harmful

  • J. Neal Richter
  • Alden Wright
  • John Paxton
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 5199)


Beginning with the early days of the genetic algorithm and the schema theorem it has often been argued that the crossover operator is the more important genetic operator. The early Royal Road functions were put forth as an example where crossover would excel, yet mutation based EAs were subsequently shown to experimentally outperform GAs with crossover on these functions. Recently several new Royal Roads have been introduced and proved to require expected polynomial time for GAs with crossover, while needing exponential time to optimize for mutation-only EAs. This paper does the converse, showing proofs that GAs with crossover require exponential optimization time on new Ignoble Trail functions while mutation based EAs optimize them efficiently.


Genetic Algorithm Crossover Operator Exponential Time Uniform Crossover Royal Road 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer-Verlag Berlin Heidelberg 2008

Authors and Affiliations

  • J. Neal Richter
    • 1
  • Alden Wright
    • 2
  • John Paxton
    • 1
  1. 1.Montana State UniversityUSA
  2. 2.University of MontanaUSA

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