Contrary to claims by Gul and Pesendorfer (2008), I show that standard economics makes use of non-choice evidence in a meaningful way. This is because standard economics solely grounded in the theory of choice is "incomplete". That is, it has content that can not be revealed with any general...

We consider a decision maker who is unaware of objects to be sampled and thus cannot form beliefs about the occurrence of particular objects. Ex ante she can form beliefs about the occurrence of novelty and the frequencies of yet to be known objects. Conditional on any sampled objects, she can...