Yesterday, my colleague Becca Stoloff and I presented an experiment that we've been piloting to a group of fellow brain imagers. They gave us some really good feedback, but I'd say the most useful thing was forcing myself to go through the literature again and try to boil it down to about 10 minutes of cognitive neuroscience that a moderately well-educated grad student would understand. In particular, I came up with the following idea for a table that describes one way of slicing up the kids of influences on decisions we make all the time:

(draft)

I was taking a class based on (I think) Body Mind Centering® and Contact Improvisation. The teacher said something like this:

(or, My God!  It's full of LISP!)

This article presupposes a reasonable knowledge of the R statistical programming environment. I highly recommend it, but you're not going to learn the basics here! I will, however, attempt to shed some light on some technical issues you might run into when scripting with formula objects. This would most likely be for model fitting and plotting using the excellent lattice package, but I'd be happy to hear about other applications. The only reason I'm writing about this is because I have not seen any coherent explanation of this stuff anywhere.  If you know of a better write-up somewhere, please let me know!