The Use of a Variable Length Chromosome for Permutation Manipulation in Genetic Algorithms

  • Phil Robbins


Permutations are difficult to represent and manipulate as chromosomes in genetic algorithms. Simple crossover often yields illegal solutions, and repair mechanisms appear to be very disruptive. A new chromosome structure, the Variable Length Sequence (VLS), and associated operators have been developed. The rationale is that the crossover should guarantee that the resulting solution is legal, and that the effect of disruption should be reduced by the retention of genetic memory within the chromosome. VLS is applied to the travelling salesman problem (TSP), and the results compared with those obtained using the PMX and C1 operators. VLS out-performs the other operators over a wide range of parameters.


Genetic Algorithm Travel Salesman Problem Travel Salesman Problem Tour Length High Selective Pressure 
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/Wien 1995

Authors and Affiliations

  • Phil Robbins
    • 1
  1. 1.School of Computing and Information SystemsUniversity of GreenwichLondonUK

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