Do irrelevant commodities matter?

We study how to evaluate allocations independently of individual preferences over unavailable commodities. We prove impossibility results suggesting that such evaluations encounter serious difficulties. This is related to the well-known problem of performing international comparisons of standard of living across countries with different consumption goods. We show how possibility results can be retrieved with restrictions on the domain of preferences, on the application of the independence axiom or on the set of allocations to be ranked. Such restrictions appear more plausible when the objects of evaluation are allocations of composite commodities, characteristics or human functionings rather than ordinary commodities.