How do you guess how bad the rioting is going to get after the Samarra bombing? I find myself doing mental calculations along the lines of ‘x killed on day one, double that, add in some reprisals over the next week….’. B of course I don’t have any real reason to double rather than triple, and in the end I’m just making up a number that feels about the right size.
But it wouldn’t be all that hard to make more serious estimates about the likely progression of unrest. There are any number of riots around the world triggered by some event or other, and the newspapers don’t do a bad job of reporting casualty numbers as they change. So you could get a good, quantitative, idea of how these things develop just by totalling up the figures. And shiny charts and graphs would be equally easy.
I suspect that if you did this, you’d find that certain types of unrest are very predictable. I also suspect that somebody, somewhere, has already done this; I just don’t know where you’d look to find their results.