Fuzzy Modeling and Genetic Algorithms for Data Mining and Exploration

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Chapter 9 Fundamental Concepts of Genetic Algorithms

but not overwhelm the population with too much noise. Expression 9.25

shows a good default mutation probability rate.

m

r

= max



.01,

1

N



(9.25)

Here,

m

r

is the current probability of mutation

N is the population size

The mutation rate is inversely proportional to the population size, but

not less than .001 is a good default value. For a population of 125

chromosomes, this is max(.01,.008),or[.01].

New Individual Rate

In some genetic algorithms new individuals are introduced into the next

generation. These individuals have randomly valued genes (created in the

same way as the genetic algorithm’s initial ...