org.moeaframework.core.indicator
Class R2Indicator

java.lang.Object
  org.moeaframework.core.indicator.NormalizedIndicator
      org.moeaframework.core.indicator.RIndicator
          org.moeaframework.core.indicator.R2Indicator

All Implemented Interfaces:

Indicator

public class R2Indicator
extends RIndicator

Computes the R2 indicator. The R2 indicator is the expected utility evaluated across a set of uniformly-weighted utility functions. R2 is weakly compatible with the outperformance relation for any set of utility functions. Values are normalized between [-1, 1] with -1 preferred.

References:

1. Hansen, M. P. and A. Jaszkiewicz (1998). Evaluating the Quality of Approximations to the Non-dominated Set. IMM Technical Report IMM-REP-1998-7.

Nested Class Summary

Nested classes/interfaces inherited from class org.moeaframework.core.indicator.RIndicator

RIndicator.ChebychevUtility, RIndicator.LinearWeightedSumUtility, RIndicator.UtilityFunction

Field Summary

Fields inherited from class org.moeaframework.core.indicator.RIndicator

utilityFunction, weights

Fields inherited from class org.moeaframework.core.indicator.NormalizedIndicator

problem

Constructor Summary

R2Indicator(Problem problem, int subdivisions, NondominatedPopulation referenceSet)
Constructs a new R2 indicator using the Chebychev utility function.

R2Indicator(Problem problem, int subdivisions, NondominatedPopulation referenceSet, RIndicator.UtilityFunction utilityFunction)
Constructs a new R2 indicator using the specified utility function.

Method Summary

double

evaluate(NondominatedPopulation population) Returns the value of this unary quality indicator given the specified non-dominated population.

Methods inherited from class org.moeaframework.core.indicator.RIndicator

expectedUtility, getDefaultSubdivisions

Methods inherited from class org.moeaframework.core.indicator.NormalizedIndicator

getNormalizedReferenceSet, normalize

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

R2Indicator

public R2Indicator(Problem problem,
                   int subdivisions,
                   NondominatedPopulation referenceSet)

Constructs a new R2 indicator using the Chebychev utility function.

Parameters:

problem - the problem

subdivisions - the number of subdivisions along each objective

referenceSet - the reference set

R2Indicator

public R2Indicator(Problem problem,
                   int subdivisions,
                   NondominatedPopulation referenceSet,
                   RIndicator.UtilityFunction utilityFunction)

Constructs a new R2 indicator using the specified utility function.

Parameters:

problem - the problem

subdivisions - the number of subdivisions along each objective

referenceSet - the reference set

utilityFunction - the utility function

Method Detail

evaluate

public double evaluate(NondominatedPopulation population)

Description copied from interface: Indicator

Returns the value of this unary quality indicator given the specified non-dominated population.

Parameters:

population - the non-dominated population to be evaluated

Returns:

the value of this quality indicator given the specified non-dominated population