Weighted Utilitarianism over Finite Streams

In this paper, we examine the axiomatic basis of a key result on weighted utilitarianism over finite streams. We show that a social preference order satisfies the axioms of Weak Pareto, Minimal Individual Symmetry, Shift Invariance and a new axiom, No Gap, if and only if the order has a weighted utilitarian representation. Our characterization result uniquely constructs the social welfare weights from the preference order making comparative statics analysis possible for the representation. We show with an example that dropping No Gap axiom results in no representation. As such, our axiomatization is tight, and many available characterizations of weighted utilitarianism follows from our result.