What sort of situation are you thinking of where X would be better than Y for one person and worse for none, but Y better than X all things considered?
I think of the concept of Pareto optimality as being useless because the path between the initial allocation, and a really good allocation, is usually littered with Pareto-optimums that must be broken through to get to the really good allocation. The really-good allocation is itself presumably Pareto-optimal. But you shouldn’t get into the habit of thinking that’s worth much.
Would you agree that a worthwhile concept of optimality would imply that there are no Pareto improvements that can be made to an optimum? (Though the optimum may not be Pareto superior to all alternatives.)
Not if more than a dozen people are involved. Certainly not if a million people are involved.
EDIT: Oops. Wrong.
What sort of situation are you thinking of where X would be better than Y for one person and worse for none, but Y better than X all things considered?
Doh! You’re right.
I think of the concept of Pareto optimality as being useless because the path between the initial allocation, and a really good allocation, is usually littered with Pareto-optimums that must be broken through to get to the really good allocation. The really-good allocation is itself presumably Pareto-optimal. But you shouldn’t get into the habit of thinking that’s worth much.
Would you agree that a worthwhile concept of optimality would imply that there are no Pareto improvements that can be made to an optimum? (Though the optimum may not be Pareto superior to all alternatives.)
Yes, within the assumptions of the Pareto model.