Selection and Reduction

Selectors are HeuristicLab 3.3 operators that implement the ISelector interface. Likewise, Reducers implement the IReducer interface.

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1. Selection Operators

Common Operator Parameters:

Parameter	Description
CopySelected	True if the selected sub-scopes should be copied, otherwise false.
CurrentScope	The current scope from which sub-scopes should be selected.
Maximization	True if the current problem is a maximization problem, otherwise false.
NumberOfSelectedSubScopes	The number of sub-scopes which should be selected.
Quality	The quality value contained in each sub-scope which is used for selection.

1.1 BestSelector

A selection operator which considers a single double quality value and selects the best.

1.2 GenderSpecificSelector

Brings two parents together by sampling each with a different selection scheme (Wagner and Affenzeller 2005).

1.3 LinearRankSelector

A linear rank selection operator which considers the rank based on a single double quality value for selection.

1.4 ProportionalSelector

A quality proportional selection operator which considers a single double quality value for selection.

1.5 RandomSelector

A random selection operator.

1.6 TournamentSelector

A tournament selection operator which considers a single double quality value for selection.

1.7 WorstSelector

A selection operator which considers a single double quality value and selects the worst.

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2. Reduction Operators

Common Operator Parameters:

Parameter	Description
CurrentScope	The current scope from which sub-scopes should be selected.

2.1 LeftReducer

An operator which reduces to the sub-scopes of the leftmost sub-scope of the current scope.

2.2 MergingReducer

An operator which reduces to the sub-scopes of all sub-scopes of the current scope.

2.3 RightChildReducer

Merges all sub-scopes generated by successively selecting sub-scopes of the remaining part.

2.4 RightReducer

An operator which reduces to the sub-scopes of the rightmost sub-scope of the current scope.

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References

• Wagner, S. and Affenzeller, M. 2005. SexualGA: Gender-Specific Selection for Genetic Algorithms. Proceedings of the 9th World Multi-Conference on Systemics, Cybernetics and Informatics (WMSCI), pp. 76-81.