A decision maker is asked to express her beliefs by assigning probabilities to certain possible states. We focus on the relationship between her database and her beliefs. We show that if beliefs given a union of two databases are a convex combination of beliefs given each of the databases, the...

Several authors have indicated a contradiction between consistent aggregation of subjective beliefs and tastes, and a Pareto condition. We argue that the Pareto condition that implies the contradiction is not compelling. Society should not necessarily endorse a unanimous choice when it is based...

An individual is asked to assess a real-valued variable y based on certain characteristics x = (x1,..., xm), and on a database consisting of n observations of (x1,..., xm, y). A possible approach to combine past observations of x and y with the current values of x to generate an assessment of...

Several authors have indicated a contradiction between consistent aggregation of subjective beliefs and tastes, and a Pareto condition. We argue that the Pareto condition that implies the contradiction is not compelling. Society should not necessarily endorse a unanimous choice when it is based...