This thesis is divided into two parts. The first part considers and develops some of the statistics used in genetic programming (GP) while the second uses those statistics to study and develop a form of incremental evolution and an early termination heuristic for GP. The first part looks in detail at success proportion, Koza's minimum computational effort, and a measure we rename "success effort". We describe and develop methods to produce confidence intervals for these measures as well as confidence intervals for the difference and ratio of these measures. The second part studies Jackson's fitness-based incremental evolution. If the number of fitness evaluations are considered (rather than the number of generations) then we find some potential benefit through reduction in the effort required to find a solution. We then automate the incremental evolution method and show a statistically significant improvement compared to GP with automatically defined functions (ADFs). The success effort measure is shown to have the critical advantage over Koza's measure as it has the ability to include a decreasing cost of failure. We capitalise on this advantage by demonstrating an early termination heuristic that again offers a statistically significant advantage.
Identifer | oai:union.ndltd.org:ADTP/225566 |
Date | January 2007 |
Creators | Walker, Matthew Garry William |
Source Sets | Australiasian Digital Theses Program |
Language | English |
Detected Language | English |
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