1. The document models the selection pressure and takeover time of the XCS learning algorithm under proportionate and tournament selection. Differential equations are derived and solved to obtain closed-form expressions for takeover time.
2. The models are validated experimentally on single-niche and multiple-niche problems. The results show the models accurately predict takeover time in general scenarios.
3. The models support previous findings that tournament selection is more robust than proportionate selection, and that sufficient fitness separation is needed for proportionate selection to identify the best classifier.
GECCO'2007: Modeling Selection Pressure in XCS for Proportionate and Tournament Selection
1. Modeling Selection Pressure in XCS for Proportionate and Tournament Selection Albert Orriols-Puig 1,2 Kumara Sastry 2 Pier Luca Lanzi 1,3 David E. Goldberg 2 Ester Bernadó-Mansilla 1 1 Research Group in Intelligent Systems Enginyeria i Arquitectura La Salle, Ramon Llull University 2 Illinois Genetic Algorithms Laboratory Department of Industrial and Enterprise Systems Engineering University of Illinois at Urbana Champaign 3 Dipartamento di Elettronica e Informazione Politecnico di Milano
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24. Results on the Single-Niche Problem Enginyeria i Arquitectura la Salle 1. Description of XCS 2. Modeling Takeover Time 3. Comparing the two Models 4. Experimental Validation 5. Modeling Generality 6. Conclusions Accuracy ratio: ρ = 0.01 RWS Tournament s=9 Tournament s=3 Tournament s=2
25. Results on the Single-Niche Problem Enginyeria i Arquitectura la Salle 1. Description of XCS 2. Modeling Takeover Time 3. Comparing the two Models 4. Experimental Validation 5. Modeling Generality 6. Conclusions Accuracy ratio: ρ = 0.50 RWS Tournament s=9 Tournament s=3 Tournament s=2
26. Results on the Single-Niche Problem Enginyeria i Arquitectura la Salle 1. Description of XCS 2. Modeling Takeover Time 3. Comparing the two Models 4. Experimental Validation 5. Modeling Generality 6. Conclusions Accuracy ratio: ρ = 0.90 RWS Tournament s=9 Tournament s=3 Tournament s=2
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34. Results of the Extended Model on the one-niched Problem Enginyeria i Arquitectura la Salle 1. Description of XCS 2. Modeling Takeover Time 3. Comparing the two Models 4. Experimental Validation 5. Modeling Generality 6. Conclusions RWS Tournament
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37. Modeling Selection Pressure in XCS for Proportionate and Tournament Selection Albert Orriols-Puig 1,2 Kumara Sastry 2 Pier Luca Lanzi 2 David E. Goldberg 2 Ester Bernadó-Mansilla 1 1 Research Group in Intelligent Systems Enginyeria i Arquitectura La Salle, Ramon Llull University 2 Illinois Genetic Algorithms Laboratory Department of Industrial and Enterprise Systems Engineering University of Illinois at Urbana Champaign
Editor's Notes
In this work, we revisit the comparison between proportionate and tournament selection. In this case, under some assumptions, we derive a model of both selection schemes that permits us to compare them.