By taking sets of utility functions as a primitive description of agents, we define an ordering over the measurability classes of assumptions on utility functions. Cardinal and ordinal assumptions constitute two types of measurability classes, but several standard assumptions lie strictly...

Does the Pareto criterion discriminate among policy choices when the policymaker does not know the correct model of the economy? If the policymaker can specify ex ante preferences for each agent, there will typically be some policy change that improves the welfare of each agent relative to a...