P. Whigham, Canberra

Lecture
Oesterreichisches Forschungsinstitut fuer Artificial Intelligence (OeFAI)
                      Schottengasse 3, A-1010 Wien
                       Tel.+43-1-53532810,5336112
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                                VORTRAG
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Peter A. WHIGHAM, M.Sc.
University of New South Wales
Canberra
Australia


A Grammatical Genetic Learning System
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The genetic programming paradigm (GP) is a functional approach to 
inductively forming programs that describe a particular problem. 
The use of natural selection based on a fitness function for modifying
the program population has allowed many problems to be solved that 
require a non-fixed representation. 

In this seminar a learning system, inspired by GP, is described. 
A context free grammar is used to define the structure of the initial 
language and to direct crossover and mutation. This represents a form 
of declarative bias. Operators that take the initial grammar and modify 
its definition are described. These operations may be considered as a 
form of specialization, given the initial grammar describes the most
general form of a solution. Hence the learning system modifies its 
own bias during the evolution of a solution. The results using these 
operators are described for various problems. 

The use of a modified grammar for future runs is discussed as a form 
of incremental learning. This shows that the learnt grammatical changes
are representing structures of the problem that are important. 


Zeit: Dienstag, 19.September 1995, 18:30 Uhr pktl.
Ort:  OeFAI, Schottengasse 3, 1010 Wien 1.