Download presentation
Presentation is loading. Please wait.
Published byColin King Modified over 7 years ago
1
Evolutionary Computation: Advanced Algorithms and Operators
Chapter 1-6 Jang, HaYoung March 28, 2011
2
Contents Introduction to fitness evaluation
Encoding and decoding functions Competitive fitness evaluation Complexity-based fitness evaluation Multiobjective optimization Introduction to constraint-handling techniques
3
Contents Introduction to fitness evaluation
Encoding and decoding functions Competitive fitness evaluation Complexity-based fitness evaluation Multiobjective optimization Introduction to constraint-handling techniques
4
Fitness Evaluation Optimization problem as follows:
Fitness evaluation function as follows: In binary coding,
5
Contents Introduction to fitness evaluation
Encoding and decoding functions Competitive fitness evaluation Complexity-based fitness evaluation Multiobjective optimization Introduction to constraint-handling techniques
6
Binary Strings N object variables x = (x1, x2, …, xn) into a binary string Decoding scheme Decoding function linearly maps the decoded integer value of the binary substring in the desired interval [ui, vi)
7
Gray Coded Strings Encoding binary string into Gray code
Decoding Gray code into binary string
8
Messy Coding Gene position and the corresponding bit values are coded in a string
9
Floating Point Coding Mantissa and exponent of a floating-point parameter Decoding
10
Coding for … Binary Variables Permutation problems Control problems
Presence or absence Permutation problems TSP Control problems Time or frequency dependent function of some control variables
11
Contents Introduction to fitness evaluation
Encoding and decoding functions Competitive fitness evaluation Complexity-based fitness evaluation Multiobjective optimization Introduction to constraint-handling techniques
12
Competitive Fitness Evaluation
Objective Fitness Is ‘absolute objective’ or complete ordering is always possible? Relative Fitness Direct comparison to some other solution either evolved or provided as a component of the environment Competitive Fitness Sensitive to the contents of the population
13
Contents Introduction to fitness evaluation
Encoding and decoding functions Competitive fitness evaluation Complexity-based fitness evaluation Multiobjective optimization Introduction to constraint-handling techniques
14
Model Selection Criteria
Minimal description length criterion Tradeoff between residual error Model complexity including a structure estimation term for the final model Number of bits necessary to encode the observations Number of bits needed to encode the parameters of the model
15
Model Selection Criteria
Akaike information criterion Approximation of the idealized Kullback-Leibler distance between the true data and the model Minimum message length Inferred estimates of the unknown parameters Data using an optimal code based on the data probability distribution
16
Minimum Descirption Legnth based Fitness Evaluation for Genetic Programming
Six multiplexor problem
17
Minimum Descirption Legnth based Fitness Evaluation for Genetic Programming
18
Contents Introduction to fitness evaluation
Encoding and decoding functions Competitive fitness evaluation Complexity-based fitness evaluation Multiobjective optimization Introduction to constraint-handling techniques
19
Contents Introduction to fitness evaluation
Encoding and decoding functions Competitive fitness evaluation Complexity-based fitness evaluation Multiobjective optimization Introduction to constraint-handling techniques
20
Search Space and Feasible and Infeasible Parts
21
Constraint Handling Techniques
Penalize infeasible individiuals Change the topology of the search space Repair infeasible solution Start with an initial population of feasible individuals Process solutions and constraints separately Locate feasible solutions
Similar presentations
© 2025 SlidePlayer.com. Inc.
All rights reserved.