source detection and decision theory

I spent a good chunk of the day figuring out how detection of isolated sources in astronomical imaging relates to the Bayesian evidence, and then decision theory. I am nearly there. The nice thing is that if you see it as a subject in decision theory, you can infer things about investigators' utility by looking at the likelihood cut at which they cut off their catalogs. In the short term, it is teaching me something about measure theory in practice.