The first set isn’t bad–it goes much beyond what I could’ve done even four years ago–but I think the second set is much improved (thanks to Yair and others). While all this was happening, I also was learning more about decision analysis. In particular, Dave Krantz convinced me that the central unit of decision analysis is not the utility function or even the decision tree but rather the goal. Applying this idea to the present discussion: what is the goal of a graph? There can be several, and there’s no reason to suppose that the graph that is best for achieving one of these goals will be optimal, or even good, for another.