allocation efficiency

allocation efficiency　分配效率　

the situation that occurs when no resources are wasted-when no one can be made better off without making someone else worse off.Allocative efficiency in any activity is achieved where any reallocation would lead to a decline in net benefit.It is achieved where marginal benefit equals marginal cost.Private efficiency is achieved where marginal private benefit equals marginal private cost（MB=MC）.Social efficiency is achieved where marginal social benefit equals marginal social cost（MSB=MSC）.