On social welfare orders satisfying anonymity and asymptotic density-one Pareto

We study the nature (i.e., constructive as opposed to non-constructive) of social welfare orders on infinite utility streams, and their representability by means of real-valued functions. We assume finite anonymity and introduce a new efficiency concept we refer to as asymptotic density-one Pareto. We characterize the existence of representable and constructive social welfare orders (satisfying the above properties) in terms of easily verifiable conditions on the feasible set of one-period utilities.