Sorry to interrupt a perfectly lovely conversation. I just have a few things to add:

• I may have overstated the case in my first post. We have some information about print shops. Specifically, we can assign very small books to print shops with a high degree of confidence. (The catch is that small books don't tend to survive very well. The remaining population is rare and intermittent in terms of production date.)

• There are some hypotheses that could be treated as priors, but they're very rarely quantified (projects like this are rare in today's humanities).