This paper estimates the elasticity of substitution between capital and skill using variation across U.S. counties in … immigration-induced skill-mix changes between 1860 and 1930. We find that capital began as a q-complement for skilled and … parametric production function calibrated to our estimates imply the level of capital-skill complementarity after 1890 likely …

1978 to 1990. Using a quadratic cost function, six production factors are distinguished : capital, energy, three types of …