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Organic Evolution and Problem Solving. Je-Gun Joung. 1.2 Evolutionary Algorithms and Artificial Intelligence. A definition of artificial Intelligence by Rich Artificial Intelligence is the study of how to make computers do things at which, at the moment, people are better.
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Organic Evolution and Problem Solving Je-Gun Joung
1.2 Evolutionary Algorithms and Artificial Intelligence • A definition of artificial Intelligence by Rich Artificial Intelligence is the study of how to make computers do things at which, at the moment, people are better. • Some researchers in AI propose to orientate toward imitation of the much more restricted capabilities of less complex animals
Representation • The symbolic period of AI can be dated period from 1962 until 1975. • A knowledge-intensive period from 1976 until 1988. • Currently, the field of AI is starting to spread research into a variety of directions • Subsymbolic period of AI dates from 1950 until 1965. • Evolutionary Algorithms make use of a subsymbolic representation of knowledge encoded in the genotypes of individuals
Learning Characteristic • Rote learning: No inference processes take place. Instead, direct implantation of knowledge is performed. • Learning by instruction: This term denotes knowledge acquisition from a teacher or from an organized source and integration with existing knowledge. • Learning by deduction: Deductive, truth-preserving inferences and memorization of useful conclusions are summarized by this term
Learning Characteristic (2) • Learning by analogy: The transformation of existing knowledge that bears strong similarity to the desired new concept into a form effectively useful in the new situation • Learning by induction: Inductive inferences • Learning from examples (concept acquisition) • Learning by observation and discovery (descriptive generalization, unsupervised learning)
Artificial Life • Artificial Life research concentrates on computer simulations of simple hypothetical life forms • The problem how to make their behavior adaptive. • Self-organizing properties emerging from local interactions within a large number of simple basic agents are investigated. • Analogies to natural systems can be drawn on a variety of different levels. • In many cases the agents are equipped with internal rules of strategies determining their behavior
1.4 Early Approaches • Attempts to model natural evolution as a method for searching for good solutions of problems defined on vast search spaces. • Very restricted computer power was available at that time • Automatic programming, sequence prediction, numerical optimization, and optimal control
Automatic Programming • Finding a program which calculate a certain input-output function • An attempt towards evolving computer programs as performed by Friedberg et al. In 1958 • Binary encoded • Modification by instruction interchange and random changes of instructions • “Success number” for instructions • The mutation rate depended on the success numbers
Automatic Programming (2) • Selective pressure • To test different programs created by random instruction changes and instruction interchanges • To choose the best of the new programs as the next starting point. • The approach measured quality of the program by combining the binary feedback information
Optimization • Bremermann’s work was more oriented towards optimization in 1962. • Multiple mutations are necessary to overcome “points of stagnation” • Optimal mutation probability-1/l
Evolutionary Programming • Forgel: 1964 • A more complicated application domain • A sequence prediction problem ( finite-state-machine: FSM) • Population-based algorithm
Evolutionary Operation (EVOP) • EVOP approach as presented by Box in 1957. • This method emphasized on the natural model of the organic evolution by performing a mutation-selection process. • ( ) -strategy (where or , the so-called 22 and 23 factorial design method
1.5 Summary • The basic process of transcription and translation , the genetic code and the hierarchical structure of genetic information • In connection to meiotic heredity, the crossover mechanism and the various forms of mutation • Evolution processes on the lower level of biological macromolecules
Summary • Evolutionary algorithms are inductive learning algorithms that can serve as a powerful search method in many fields of AI research. • Three examples of global optimization problems • Computational complexity of global optimization problems • The early approaches