Bayes Ball!

A good illustration of Bayesian conditional networks:

http://www.cs.ubc.ca/~murphyk/Bayes/Figures/bayes_ball_no_det.gif

Using ArcGIS to document work products

When using ArcGIS, it's not always possible to name a given piece of data in a way that retains all the information on how it was generated--what the inputs were, how raster values were calculated, etc. Ideally, a log would be kept to document this sort of information.

Another option is embedded right in Arc: the Results pane. If you save the .mxd after every process you run, all the information you need is retained there.

(It's probably still good to keep a log for important data, especially if files might be moved or renamed.)