ThresholdScaleFitness: Dispersion Ratio Based Threshold Fitness Scaling.

In xegaSelectGene: Selection of Genes and Gene Representation Independent Functions

Dispersion Ratio Based Threshold Fitness Scaling.

Description

Fitness is transformed by a power function with a scaling exponent. The choice of the scaling exponent depends on the ratio of the dispersion measures of the current and the previous population fitness.

Usage

ThresholdScaleFitness(fit, lF)

Arguments

fit	Fitness vector.
lF	Local configuration.

Details

The scaling exponent is selected by the following rule:

• If lF$RDM()>1+lF$ScalingThreshold() then choose the scaling exponent lF$ScalingExp(). The scaling exponent should be larger than 1 to increase the selection pressure.

• If lF$RDM()<1+lF$SCalingThreshold and lF$RDM()>1-lF$SCalingThreshold, the fitness is not scaled.

• If lF$RDM()<1-lF$SCalingThreshold then choose the scaling exponent lF$ScalingExp2(). The scaling exponent should be smaller than 1 to decrease the selection pressure.

Value

Scaled fitness vector.

See Also

Other Scaling: ContinuousScaleFitness(), DispersionRatio(), ScaleFitness(), ScalingFitness()

Other Adaptive Parameter: ContinuousScaleFitness()

Examples

lF<-list()
lF$Offset<-parm(0.0001)
lF$ScalingThreshold<-parm(0.05)
lF$RDM<-parm(1.0)
lF$ScalingExp<-parm(2.0)
lF$ScalingExp2<-parm(0.5)
fit<-sample(10, 20, replace=TRUE)
fit
ThresholdScaleFitness(fit, lF)
lF$RDM<-parm(1.2)
ThresholdScaleFitness(fit, lF)
lF$RDM<-parm(0.8)
ThresholdScaleFitness(fit, lF)

xegaSelectGene documentation built on April 16, 2025, 5:12 p.m.