EFFICIENCY

In general, efficiency is the ratio of a system+s output (or production) to input, as in the useful energy produced by a system compared to the energy put in the system. In ecology, it is the percentage of useful energy transferred from one trophic level to the next (as in the ratio of production of herbivores to that of primary producers). Used in the context of production, efficiency is the ratio of useful work performed to the total energy expended, thus avoiding waste generation. In the context of the allocation of resources, efficiency is the condition which would make at least one person better off and no one worse off. This implies that some may get richer and others not improve their status. Scialabba (1998)