ICA Page
Independent Components Analysis

Data exploration, dimension reduction, separating mixed signals, automatic feature extraction - all are common techniques used across many domains of science in order to represent data so that it can be understood and easily managed or manipulated. Over the past few years, ICA has become an important tool for doing these tasks.

ICA SIG - An ICA SIG (Special Interest Group) has been formed for L.I.T. researchers- we meet approximately every two weeks, discuss papers, basics, applications, etc. Please see below if you would like to be on our mailing list or participate.

Please see the Graphical Models page for information about this related are of interest.


Introduction to ICA
    0) Necessary background
    1) One-page intro by Te-Won Lee
    2) One-chapter intro from Aapo Hyvärinen and Erkki Oja

ICA Links
    ICA Central (Cardoso)
    Paris Smaragdis' page full of links
    Tony Bell's Salk Institute, Computational Neurobiology Laboratory

Code Resources
    MATLAB and C code (Infomax from Bell and Sejnowski and more)
    BLISS  Java and MATLAB code (including techniques for nonlinear mixtures)
    FAST ICA from the Finland ICA Mafia - The most popular quick-and-easy tool for exploring ICA.

Applications
    Text Mining, Face Recognition, Cocktail Party Phenomenon, fmri separation, Noise Cancellation, Classification, MPEG-7 description, Preprocessing for Neural Networks, Kitchen Sink washing.


Background Knowledge

Some of the basics you'll need to be familiar with to delve into ICA are:

PCA - Principle Components Analysis: an old and standard technique for data analysis and dimension reduction

Other basic statistical concepts:
    Mean, Variance, Standard Deviation, higher-order moments, cumulants.
    Correlation, covariance, cross correlation, cross variance.

SVD - Singular Value Decomposition - a basic matrix manipulation technique that has many purposes including computational linear system of equation solving, stability analysis, and dimension reduction.

The best place to find clear explanations of these things is in undergraduate textbooks.
A on-line resource for math basics is:  http://mathworld.wolfram.com/letters/ (see the subject index)
Numerical Recipes has a good discussion of SVD.
MATLAB is excellent for exploring, plotting, seeing how things work.



ICA SIG

Contact : Lonce Wyse

Seminar Series
Here are the two zipped PowerPoint slides from the ICA intro seminar talks given at KRDL and the math dept. in March:
Slides from talk 1
Slides from talk 2
They aren't really very self-contained without the discussion and the demos, but they may be useful anyway, especially if you are creating a presentation yourself!

Last updated: $Date: 2002/01/31 $

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