Free cookie consent management tool by TermsFeed Policy Generator

Changes between Version 1 and Version 2 of Crossover


Ignore:
Timestamp:
06/08/10 18:26:57 (14 years ago)
Author:
mkofler
Comment:

Updated crossover descriptions

Legend:

Unmodified
Added
Removed
Modified
  • Crossover

    v1 v2  
    77=== !MultiBinaryVectorCrossover ===
    88Randomly selects and applies one of its crossovers every time it is called.
    9 
    10 
    11 '''Operator Parameters:'''
    12 
    13 ||= Parameter         =||= Description =||
    149
    1510=== NPointCrossover ===
     
    7166
    7267----
     68== Crossover for !RealVectorEncoding ==
     69=== !AverageCrossover ===
     70The average crossover (intermediate recombination) produces a new offspring by calculating in each position the average of a number of parents. It is implemented as described by (Beyer and Schwefel 2002).
     71
     72=== !BlendAlphaBetaCrossover ===
     73The blend alpha beta crossover (BLX-a-b) for real vectors is similar to the blend alpha crossover (BLX-a), but distinguishes between the better and worse of the parents. The interval from which to choose the new offspring can be extended more around the better parent by specifying a higher alpha value. It is implemented as described in (Takahashi and Kita 2001).
     74
     75=== !BlendAlphaCrossover ===
     76The blend alpha crossover (BLX-a) for real vectors creates new offspring by sampling a new value in the range [min_i - d * alpha, max_i + d * alpha) at each position i. Here min_i and max_i are the smaller and larger value of the two parents at position i and d is max_i - min_i. It is implemented as described in (Takahashi and Kita 2001).
     77
     78=== !DiscreteCrossover ===
     79Discrete crossover for real vectors: Creates a new offspring by combining the alleles in the parents such that each allele is randomly selected from one parent. It is implemented as described in (Beyer and Schwefel 2002).
     80
     81=== !HeuristicCrossover ===
     82The heuristic crossover produces offspring that extend the better parent in direction from the worse to the better parent. It is implemented as described in (Wright 1994).
     83
     84=== !LocalCrossover ===
     85The local crossover is similar to the arithmetic all positions crossover, but uses a random alpha for each position x = alpha * p1 + (1-alpha) * p2. It is implemented as described in (Dumitrescu et al. 2000, p. 194).
     86
     87=== !MultiRealVectorCrossover ===
     88Randomly selects and applies one of its crossovers every time it is called.
     89
     90=== !RandomConvexCrossover ===
     91The random convex crossover acts like the local crossover, but with just one randomly chosen alpha for all crossed positions. It is implementes as described in (Dumitrescu et al. 2000, pp. 193 - 194).
     92
     93=== !SimulatedBinaryCrossover ===
     94The simulated binary crossover (SBX) is implemented as described in (Deb and Agrawal 1995).
     95
     96=== !SinglePointCrossover ===
     97Breaks both parent chromosomes at a randomly chosen point and assembles a child by taking one part of the first parent and the other part of the second pard. It is implemented as described in (Michalewicz 1999).
     98
     99=== !UniformAllPositionsArithmeticCrossover ===
     100The uniform all positions arithmetic crossover constructs an offspring by calculating x = alpha * p1 + (1-alpha) * p2 for every position x in the vector. Note that for alpha = 0.5 it is the same as the !AverageCrossover. It is implemented as described in (Michalewicz 1999).
     101
     102=== !UniformSomePositionsArithmeticCrossover ===
     103The uniform some positions arithmetic crossover (continuous recombination) constructs an offspring by calculating x = alpha * p1 + (1-alpha) * p2 for a position x in the vector with a given probability (otherwise p1 is taken at this position). It is implemented as described in (Dumitrescu et al. 2000, p. 191). Note that Dumitrescu et al. specify the alpha to be 0.5.
     104
     105----
     106== Crossover for !SymbolicExpressionTreeEncoding ==
     107=== !SubTreeCrossover ===
     108An operator which performs subtree swapping crossover.
     109----
    73110== References ==
    74111 * Affenzeller, M. et al. 2009. Genetic Algorithms and Genetic Programming - Modern Concepts and Practical Applications. CRC Press.
     112 * Beyer, H.-G. and Schwefel, H.-P. 2002. Evolution Strategies - A Comprehensive Introduction Natural Computing, 1, pp. 3-52.
     113 * Deb, K. and Agrawal, R. B. 1995. Simulated binary crossover for continuous search space. Complex Systems, 9, pp. 115-148.
     114 * Dumitrescu, D. et al. 2000. Evolutionary computation. CRC Press. Boca Raton. FL.
    75115 * Eiben, A.E. and Smith, J.E. 2003. Introduction to Evolutionary Computation. Natural Computing Series, Springer-Verlag Berlin Heidelberg.
    76116 * Fogel, D.B. 1988. An Evolutionary Approach to the Traveling Salesman Problem. Biological Cybernetics, 60, pp. 139-144, Springer-Verlag.
     
    79119 * Mühlenbein, H. 1991. Evolution in time and space - the parallel genetic algorithm. FOUNDATIONS OF GENETIC ALGORITHMS. Morgan Kaufmann. pp. 316-337.
    80120 * Syswerda, G. 1991. Schedule Optimization Using Genetic Algorithms. In Davis, L. (Ed.) Handbook of Genetic Algorithms, Van Nostrand Reinhold, New York, pp. 332-349.
     121 * Takahashi, M. and Kita, H. 2001. A crossover operator using independent component analysis for real-coded genetic algorithms Proceedings of the 2001 Congress on Evolutionary Computation, pp. 643-649.
    81122 * Wendt, O. 1994. COSA: COoperative Simulated Annealing - Integration von Genetischen Algorithmen und Simulated Annealing am Beispiel der Tourenplanung. Dissertation Thesis. IWI Frankfurt.
    82123 * Whitley et.al. 1991, The Traveling Salesman and Sequence Scheduling, in Davis, L. (Ed.), Handbook of Genetic Algorithms, New York. pp. 350-372
     124 * Wright, A.H. 1994. Genetic algorithms for real parameter optimization, Foundations of Genetic Algorithms. G.J.E. Rawlins (Ed.). Morgan Kaufmann. San Mateo. CA. pp. 205-218.