Title
Analyzing phase transitions in high-dimensional self-organizing maps
Abstract
.  The self-organizing map (SOM), a widely used algorithm for the unsupervised learning of neural maps, can be formulated in a low-dimensional ‘feature map’ variant which requires prespecified parameters (‘features’) for the description of receptive fields, or in a more general high-dimensional variant which allows self-organization of the structure of individual receptive fields as well as their arrangement in a map. We present here a new analytical method for deriving conditions for the emergence of structure in SOMs which is particularly suited for the as yet inaccessible high-dimensional SOM variant. Our approach is based on an evaluation of a map distortion function. It involves only an ansatz for the way stimuli are distributed among map neurons; the receptive fields of the map need not be known explicitly. Using this method we first calculate regions of stability for four possible states of SOMs projecting from a rectangular input space to a ring of neurons. We then analyze the transition from nonoriented to oriented receptive fields in a SOM-based model for the development of orientation maps. In both cases, the analytical results are well corroborated by the results of computer simulations.
Year
DOI
Venue
1996
10.1007/s004220050305
Biological Cybernetics
Keywords
Field
DocType
Phase Transition,Computer Simulation,Receptive Field,Input Space,Unsupervised Learning
Receptive field,Ansatz,Phase transition,Distortion function,Quasi-open map,Self-organizing map,Unsupervised learning,Artificial intelligence,Machine learning,Mathematics
Journal
Volume
Issue
ISSN
75
5
0340-1200
Citations 
PageRank 
References 
9
1.55
9
Authors
3
Name
Order
Citations
PageRank
Maximilian Riesenhuber176159.73
Hans-ulrich Bauer223638.94
Theo Geisel331440.09