On a criterion of infinite-horizon efficiency (Q1111454)

We prove a property of the class of programs covered by Cass' pioneering criterion of inefficiency of infinite-horizon programs [see \textit{D. Cass}, J. Econ. Theory 4, 200-223 (1972)]. A notion that we call gross inefficiency is introduced. It is, in general, a much stronger property than inefficiency. We then show that a program in the class studied by Cass is inefficient if and only if it is grossly inefficient.