0000000000433417
AUTHOR
Pasi Koikkalainen
Tree Structured Self-Organizing Maps
Publisher Summary This chapter provides an overview of the tree structured self-organizing maps (TS-SOM). It was originally intended as a fast implementation of the self-organizing map (SOM). The chapter explains that TS-SOM is a constructive smoother for a class of dimension reduction problems. There is a well known relation between self-organizing maps and principal curves. Unfortunately in most presentations it is derived by simple reasoning, avoiding the mathematical statement of the problem, which is essential to understand how efficient SOM implementations can be constructed. In this chapter, SOM is derived as a numerical solution of a generic model in a continuous domain, which diffe…
Complexity Selection of the Self-Organizing Map
This paper describes how the complexity of the Self-Organizing Map can be selected using the Minimum Message Length principle. The use of the method in textual data analysis is also demonstrated.
A Parallel Implementation of the Tree-Structured Self-Organizing Map
This paper presents how Self-Organizing Maps (SOMs)can be trained efficiently using several, simultaneously executing threads on a shared memory Symmetric MultiProcessing (SMP)computer. The training method is a batch version of the Tree-Structured Self-Organizing Map. We note that SMP type of parallel training is very useful for large data sets obtained from nature, the process industry or large document collections, since we do not encounter similar model size limitations as with hardware SOM implementations.
Analysis of Multi-Choice Questionnaires through Self-Organizing Maps
This paper describes how Self-Organizing Maps can be used to analyse multi-choice gallups. In this method, the use of a single SOM for all available data is replaced with the use of multiple SOMs trained with subsets of gallup questions. The subgroupings located from these maps are then used to train a new concluding SOM that is more readable than any single SOM analysis would be.
An automatic quality system for injection molding
This paper describes a fully automatic quality system for injection molding. The proposed system includes an on-line measurement platform with a digital camera, a methodology for adaptive design of experiments (DOE), statistical modeling, process monitoring, and a closed loop process control. The system has been tested in the manufacturing of plastic parts for mobile phones.