Topological Properties of the Efficient Point Set
Bezalel Peleg · Proceedings of the American Mathematical Society · 1972
Let y be a closed and convex subset of a Euclidean space. We prove that the set of efficient points of Y, $M(Y)$, is contractible. Furthermore, if $M(Y)$ is closed (compact) then it is a retract of a convex closed (compact) set. Our proof relies on the Arrow-Barankin-Blackwell Theorem. A new proof is supplied for that theorem.