This model, and its pragmatic decoding component in particular, is designed to avoid words that are specific to categories when there is uncertainty about the category of a target object, in favour of words that are not specific to categories like, e.g., colour or location attributes.
we assume that our listener has hidden beliefs about the category of the referent, that we can marginalize over as follows: As a simplification, we condition u only on c i , instead of P (u|c i , r).