Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
The transformation relationship between factor inputs and outputs - the efficient production frontier (EPF)- contains important information for fisheries managers. A directional technology distance function model of the harvesting technology is used to measure changes in the EPF over time. Frontier shifts are summarized with input- and output-based frontier indicators that are interpreted as measures of bioeconomic productivity change. The model is applied to the Mid-Atlantic surf clam and ocean quahog fishery.