Mitchell, T. J. (2010) An exploration of evolutionary computation ...

Contents
1 Introduction .………………………………………………………………….. 1
1.1 Context …………………………………………………………………………………..……. 2
1.1.1 Evolutionary Optimisation …………………………………………………………. 3
1.1.2 Frequency Modulation Audio Synthesis …………………………………………… 4
1.2 Objectives ……………………………………………………………………………………... 7
1.3 Contributions ………………………………………………………………………………….. 8
1.4 Methodology ………………………………………………………………………………….... 8
1.5 Thesis Structure ……………………………………………………………………………….. 9
1.6 Implementation ………………………………………………………………………………... 9
2 Background: Evolutionary Computation …………………………………….. 10
2.1 An Introduction to Evolutionary Computation ……………………………………………….. 10
2.2 The Evolutionary Algorithm ………………………………………………………………….. 11
2.3 Canonical Evolutionary Algorithms …………………………………………………………... 14
2.3.1 The Genetic Algorithm ……………………………………………………………... 14
2.3.2 Evolution Strategies ……………………………………………………………….... 17
2.3.2.1 Recombination ……………………………………………………………. 18
2.3.2.2 Genetic Repair ……………………………………………………………. 19
2.3.2.3 Mutation ………………………………………………………………….. 21
2.3.2.4 Selection ………………………………………………………………….. 27
2.4 EA Similarities and Differences ………………………………………………………………. 27
2.5 Summary of this Chapter ……………………………………………………………………… 29
3 Background - Multimodal Optimisation ……………………………………... 31
3.1 Multimodal Problem Domains and Preconvergence ………………………………………….. 31
3.2 Injecting Diversity …………………………………………………………………………….. 33
3.3 Appropriate Diversity …………………………………………………………………………. 35
3.4 Speciation …………………………………………………………………………………….... 35
3.4.1 Non Partition-Based Speciation Methods …………………………………………... 36
3.4.1.1 Similarity-Based Selection/Replacement ……………………………….... 36
3.4.1.2 Restricted Tournament selection …………………………………………. 38
3.4.2 Fitness Sharing …………………………………………………………………….... 38
3.5 Static Partition Speciation Methods ………………………………………………………….... 39
3.5.1 Coarse-Grained Parallel Population Methods - The Island Model …………………. 40
3.5.2 Fine-Grained Parallel Population Methods: The Diffusion Model …………………. 42
3.5.3 Discussion …………………………………………………………………………... 43
3.6 Dynamic-Partition Speciation Methods ……………………………………………………….. 44
3.6.1 Cluster-Based Partition Methods …………………………………………………… 44
3.6.2 Alternative Dynamic-partition Methods ……………………………………………. 48
3.7 Multimodal Optimisation with Cooperative Coevolution …………………………………….. 48
3.8 Summary of this Chapter ……………………………………………………………………… 50
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