Multivariate statistics is something I really wish was covered better. In my work as an engineer I use multiple linear regression from time to time. The best m

Multivariate statistics is something I really wish was covered better. In my work as an engineer I use multiple linear regression from time to time. The best method I've found is forward selection stepwise approach. I've never really seen a simple explanation of how it works (it was introduced to me by a statistician at my work) but it is useful when you have many variables and you want to see how significant a single variable is relative to overall regression. The impression I get is pure stats people really dislike stepwise modelling. More recently I've been looking into something called PCA (Principle Component Analysis) and PLS (projection to latent structure) after I came across it in a PHD thesis. I've yet to find a decent simple explanation about how it works though. Unfortunately my work no longer employees a statistician.