May I ask what kind of data you use PCA for?

It apperently gets more popular these days. I have seen it used for genetic chimera analysis and DNA arrays as a prelude to clustering. When I started to use it, my mentor was very sceptic about how acceptable it would be. While the statistican who helps me told me it was a technique of about a century old so nobody should complain.

Anyway, I use it for clustering analysis as well, but than for extracellularly recorded neuronal spike waveforms. So I sample spike waveforms from an electrode that was placed in a brain slice and turn a PCA routine loose on it. Mostly just the first two components are enough to get your clusters.

Jeroen
"We are not alone"(FZ)