Page 12 - 49A Field Guide to Genetic Programming

CONTENTS CONTENTS

4.2.2 Fitness Evaluation . . . . . . . . . . . . . . . . . . . . 32
4.2.3 Selection, Crossover and Mutation . . . . . . . . . . . 32
4.2.4 Termination and Solution Designation . . . . . . . . . 35

II Advanced Genetic Programming 37

5 Alternative Initialisations and Operators in Tree-based GP 39
5.1 Constructing the Initial Population . . . . . . . . . . . . . . . 39
5.1.1 Uniform Initialisation . . . . . . . . . . . . . . . . . . 40
5.1.2 Initialisation may Affect Bloat . . . . . . . . . . . . . 40
5.1.3 Seeding . . . . . . . . . . . . . . . . . . . . . . . . . . 41
5.2 GP Mutation . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
5.2.1 Is Mutation Necessary? . . . . . . . . . . . . . . . . . 42
5.2.2 Mutation Cookbook . . . . . . . . . . . . . . . . . . . 42
5.3 GP Crossover . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
5.4 Other Techniques . . . . . . . . . . . . . . . . . . . . . . . . . 46

6 Modular, Grammatical and Developmental Tree-based GP 47
6.1 Evolving Modular and Hierarchical Structures . . . . . . . . . 47
6.1.1 Automatically Defined Functions . . . . . . . . . . . . 48
6.1.2 Program Architecture and Architecture-Altering . . . 50
6.2 Constraining Structures . . . . . . . . . . . . . . . . . . . . . 51
6.2.1 Enforcing Particular Structures . . . . . . . . . . . . . 52
6.2.2 Strongly Typed GP . . . . . . . . . . . . . . . . . . . 52
6.2.3 Grammar-based Constraints . . . . . . . . . . . . . . . 53
6.2.4 Constraints and Bias . . . . . . . . . . . . . . . . . . . 55
6.3 Developmental Genetic Programming . . . . . . . . . . . . . 57
6.4 Strongly Typed Autoconstructive GP with PushGP . . . . . 59

7 Linear and Graph Genetic Programming 61
7.1 Linear Genetic Programming . . . . . . . . . . . . . . . . . . 61
7.1.1 Motivations . . . . . . . . . . . . . . . . . . . . . . . . 61
7.1.2 Linear GP Representations . . . . . . . . . . . . . . . 62
7.1.3 Linear GP Operators . . . . . . . . . . . . . . . . . . . 64
7.2 Graph-Based Genetic Programming . . . . . . . . . . . . . . 65
7.2.1 Parallel Distributed GP (PDGP) . . . . . . . . . . . . 65
7.2.2 PADO . . . . . . . . . . . . . . . . . . . . . . . . . . . 67
7.2.3 Cartesian GP . . . . . . . . . . . . . . . . . . . . . . . 67
7.2.4 Evolving Parallel Programs using Indirect Encodings . 68

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