This paper axiomatically characterizes how society under uncertainty should select collective belief systematically and how much society should be collectively ambiguity averse, where individuals are ambiguity-averse and their beliefs disagree in general. Our characterization allows two kinds of...

We propose an abstract method of systematically assigning a "rational"' ranking to non-rationalizable choice data. We define an individual welfare functional as a mapping from stochastic choice functions into weak orders. A stochastic choice function (or choice distribution) gives the empirical...

In many situations, agents are involved in an allocation problem that is followed by another allocation problem whose optimal solution depends on how the former problem has been solved. In this paper, we take this dynamic structure of allocation problems as an institutional constraint. By...