Environmental production functions and environmental directional distance functions

This study derives the relationship between environmental production functions and environmental directional distance functions. These two approaches make different assumptions when modeling the joint production of good and bad outputs. The environmental production function credits a producer solely for expanding good output production, while the directional environmental distance function credits a producer for simultaneously increasing production of the good output and reducing production of bad outputs. Estimates of technical efficiency and pollution abatement costs are calculated using data from coal-fired power plants. These results provide the empirical basis for comparing the environmental production function to the environmental directional distance function.