IMPACTS OF TECHNOLOGICAL-CHANGE ON FACTOR SUBSTITUTION BETWEEN ENERGY AND OTHER INPUTS WITHIN UNITED-STATES AGRICULTURE, 1950-79

Past efforts to estimate elasticities of substitution between inputs both in and out of agriculture have usually made use of a single data set to provide the elasticities between the input pairs, and have led to highly conflicting results, particularly with respect to the substitution between capital or machinery and energy. This study reveals that the elasticity of substitution between a number of input pairs in agriculture can vary by substantial amounts depending on the time period used for the estimation. Energy in agriculture, which was a complement for machinery in the 1950s, was a substitute by the 1970s. © 1990.