In this paper we extend Harsanyi's impartial observer theorem by showing that the large domain of social lotteries can be significantly restricted – it is sufficient that the domain consists only of constant extended lotteries. Copyright Springer-Verlag Berlin Heidelberg 2003

We provide an axiomatization of an additively separable social welfare function in the context of Harsanyi’s impartial observer theorem. To do this, we reformulate Harsanyi’s setting to make the lotteries over the identities the observer may assume independent of the social alternative....

We show that efficient anonymous incentive compatible (dominant strategy) mechanisms for public goods eliminate externalities, i.e., each individual is unable to change the welfare of anyone else. The characterization is used to derive existence and non-existence results for models with a finite...

Since Becker (<CitationRef CitationID="CR3">1971</CitationRef>), a common argument against asymmetric norms that promote minority rights over those of the majority is that such policies reduce total welfare. While this may be the case, we show that there are simple environments where aggregate sum of individual utilities is actually...</citationref>