Fair social orderings

International audienceIn a model of private good allocation, we construct social orderings which depend only on ordinal non-comparable information about individual preferences. In order to avoid Arrovian-type impossibilities, we let those social preferences take account of the shape of individual indifference curves. This allows us to introduce equity and cross-economy robustness properties, inspired by the theory of fair allocation. Combining such properties, we characterize two families of fair social orderings