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Whole arithmetic crossover

As explained in Optimization Algorithms: AI techniques for design, planning, and control problems

A crossover method that creates offspring by taking weighted arithmetic combinations of corresponding parent values.

Whole arithmetic crossover creates offspring in a real-valued genetic algorithm by taking a weighted average of every corresponding value in two parent chromosomes. A weight α between 0 and 1 controls each parent’s contribution. section 8.2.1

Child1Genei = α × Parent1Genei + (1 – α) × Parent2Genei

Child2Genei = α × Parent2Genei + (1 – α) × Parent1Genei

Use the formulas to compute both children: each child applies the same weight while reversing the parents’ roles. section 8.2.1

Worked chromosome example

For Parent1 = [1, 2, 3, 4], Parent2 = [2, 2, 2, 2], and α = 0.2, Child1 becomes [1.8, 2, 2.2, 2.4]. Reversing the parent contributions gives Child2 = [1.2, 2, 2.8, 3.6]. The first child can then undergo Gaussian mutation; with an added value of 0.43, it becomes [2.23, 2.43, 2.63, 2.83]. section 8.2.2

Apply the method as follows:

  • Choose two real-valued parent chromosomes and a weight α in [0, 1]. section 8.2.1
  • Average every corresponding gene to produce two complementary offspring. section 8.2.1
  • Evaluate the offspring and optionally apply mutation within the genetic algorithm. section 8.2.2

How Optimization Algorithms: AI techniques for design, planning, and control problems covers it

How deep it goes
Defines weighted whole-chromosome averaging and works through a four-parameter numerical example.
Examples
Uses coefficient vectors for third-order polynomial curve fitting, including explicit parents, offspring, mean-squared errors, and mutation.
What it assumes
Assumes familiarity with chromosomes, genes, parent solutions, weights, and real-valued genetic algorithms.
What you can do after
Apply it to combine real-valued candidate solutions before evaluating and mutating offspring.
How it connects
Connects real-valued genetic algorithms with arithmetic crossover, mutation, Gaussian mutation, and simulated binary crossover.

Related concepts

This explainer was generated by Manning's knowledge graph from the text of Optimization Algorithms: AI techniques for design, planning, and control problems. The section links point to the parts of the book it draws on.