ICA is a nongaussian version of factor analysis, and somewhat similar to principal component analysis. ICA has many applications in data analysis, source separation, and feature extraction.
Projection pursuit is a technique for exploratory data analysis with emphasis on visualization.
It is based on finding low-dimensional projections of multivariate data that show highly nongaussian distributions. It can be used, however, to implement classical maximum likelihood ICA estimation as well. See the FastICA home page .