genetic algorithms learning machines for knowledge discovery

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Genetic Algorithms Learning Machines for knowledge discovery

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Page 1: Genetic Algorithms Learning Machines for knowledge discovery

Genetic AlgorithmsGenetic AlgorithmsLearning Machines for knowledge discovery

Page 2: Genetic Algorithms Learning Machines for knowledge discovery

Finding Patterns in DataFinding Patterns in Data Data mining is the task of

digging through this data looking for patterns, associations or predictions and which transform that raw material into useful information.

Evolutionary algorithms evolve the patterns which fit the data using Darwinian principles to weed out the patterns which don't work in favor of those that do. Survival of the fittest ensures that over time it is the patterns which best fit the raw data that are delivered as solutions.

Page 3: Genetic Algorithms Learning Machines for knowledge discovery

Concept HierarchyConcept Hierarchy All Knowledge Computer Science Artificial Intelligence Evolutionary Computation Evolutionary Algorithms

Genetic Algorithms Genetic Programming

Page 4: Genetic Algorithms Learning Machines for knowledge discovery

Human Knowledge

Computer Science

Graphics DatabasesArtificial Intelligence Networking

Natural Language Evolutionary Computation

Math Logic Language Physics Biology

Evolutionary Algorithms

Genetic Algorithms Genetic Programming

Swarm Intelligence

Expert Systems

Page 5: Genetic Algorithms Learning Machines for knowledge discovery

TerminologyTerminology Algorithm

A finite set of rules (a procedure) that solves a problem

Evolution A series of changes in a population over time affected

by biological, chemical, environmental, and technical factors

Evolutionary Algorithm An algorithm that uses selection, crossover and

mutation to produce better and better results

Page 6: Genetic Algorithms Learning Machines for knowledge discovery

Genetic AlgorithmsGenetic Algorithms The Genetic Algorithm is a model of machine learning

Based on the theory of evolution (Darwin) Accomplished by creating a population of individuals represented by “chromosomes” within a computer

Chromosomes can be just character strings that are analogous to the base-4 chromosomes that we see in our own DNA

The individuals in the population then go through a process of evolution (sexual reproduction followed by survival pressure on offspring)

Page 7: Genetic Algorithms Learning Machines for knowledge discovery

Evolutionary ForcesEvolutionary Forces Selection

A survival process Crossover

A sexual process Mutation

A random process

Page 8: Genetic Algorithms Learning Machines for knowledge discovery

SelectionSelection

Fitness to perform Mechanisms for Selection

Survival Quantitative function Human intervention

Page 9: Genetic Algorithms Learning Machines for knowledge discovery

CrossoverCrossover

Page 10: Genetic Algorithms Learning Machines for knowledge discovery

MutationMutation

Page 11: Genetic Algorithms Learning Machines for knowledge discovery

BiomorphsBiomorphs

Visualizing and controlling mutations

http://www.phy.syr.edu/courses/mirror/biomorph/

Page 12: Genetic Algorithms Learning Machines for knowledge discovery

Genetic ProgrammingGenetic Programming

Genetic programming is the application of genetic algorithms to computer programs themselves

Proposed byJohn Koza (Stanford)

Page 13: Genetic Algorithms Learning Machines for knowledge discovery

Genetic Programming ProcessGenetic Programming Process Start with a collection of functions randomly combine them into programs run the programs and see which gives the best

results keep the best programs (natural selection) mutate some of the others test the new generation repeat this process until a clear best program

emerges

Page 14: Genetic Algorithms Learning Machines for knowledge discovery

Genetic Programming ExampleGenetic Programming Example

Data (-1,1,3,5,7,9,11,13,15,17) Input function elements

x (can equal any digit 0..9) +,-,*,/

Starting functions (x,x+0,x*2,1+3,4/2)

Page 15: Genetic Algorithms Learning Machines for knowledge discovery

Function TreeFunction Tree

x *

x3

*

x2 *

x2

+

1 *

x2

-

1

0,1,2,3,4,5,6,7,8,9

0,3,6,8,12,15,18,21,24,27

0,2,4,6,8,10,12,14,16,18

0,3,5,7,9,11,13,15,17,19

-1,1,3,5,7,9,11,13,15,17

Many more functions

Page 16: Genetic Algorithms Learning Machines for knowledge discovery

Functional ValuesFunctional ValuesTruth x 3*x 2*x 2*x+1 2*x-1

-1 0 0 0 1 -11 1 3 2 3 13 2 6 4 5 35 3 9 6 7 57 4 12 8 9 79 5 15 10 11 9

11 6 18 12 13 1113 7 21 14 15 1315 8 24 16 17 1517 9 27 18 19 17

Page 17: Genetic Algorithms Learning Machines for knowledge discovery

FitnessFitnessFitness Fitness Fitness Fitness Fitness

1 1 1 2 00 2 1 2 0-1 3 1 2 0-2 4 1 2 0-3 5 1 2 0-4 6 1 2 0-5 7 1 2 0-6 8 1 2 0-7 9 1 2 0-8 10 1 2 0

SUM -35 55 10 20 0

Page 18: Genetic Algorithms Learning Machines for knowledge discovery

Genetic Algorithms are FlexibleGenetic Algorithms are Flexible

Can solve hard problems quickly and reliably.

Can be easily adapted to data (simulations, models)

Can be extended (scalable) Can be hybridized

Page 19: Genetic Algorithms Learning Machines for knowledge discovery

GA SoftwareGA Software Evolver (for Excel)

http://www.jurikres.com/catalog/ms_evol.htmPalisade Corp