The efficiency of price income situations,the real average income — a characterization

Since efficiency represents a measure of the average welfare level of the society it is often used as a synonym of “mean income” in (traditional) welfare measurement theory and neglects price information. In this note, we introduce a rather general concept of efficiency taking price information into account. Requiring some reasonable properties for efficiency judgements we look for real indicators, namely efficiency measures. By this axiomatic approach, we easily characterize a special class of (sequences of) functions that will turn out to be the real average income.