X-Efficiency, Rent-Seeking and Social Costs

This paper investigates shifts in cost functions of monopoly and regulated firms operating under conditions of X-inefficiency and rent-seeking behavior. We show that X-inefficiency and rent seeking have significantly different implications for economic welfare. Distinctions are drawn between pecuniary and real X-inefficiency and between sunk and continuing rent-seeking costs. In general, for a given cost shift rent-seeking behavior implies larger social costs than does X-inefficiency theory. However, cost shifts caused by either X-inefficiency or rent seeking are observationally equivalent. This implies empirically measured cost shifts cannot unambiguously be attributed to either cause.