Technical efficiencies calculated using aggregated inputs are biased. It is shown empirically and analytically that input aggregation decreases calculated technical efficiencies and changes relative technical efficiencies among firms. Moreover, aggregation fails to separate technical efficiency...

Changes in individual states' agricultural production diversity and variance of cash receipts were measured over the 30-year period 1960 through 1989. Diversity was measured using a general index, of which the inverse Herfindahl and the Entropy are special cases. Cash receipt variability was...