Analyzing skilled and unskilled labor efficiencies in the US

In this paper, I analyze the time paths of the efficiencies of skilled and unskilled labor in a production framework where skilled and unskilled labor are imperfect substitutes. Their implications for economic growth and wage inequality in the US between 1950 and 2005 present two main findings. First, although skilled labor efficiency has a strong upward trend, I find no evidence of acceleration in its growth rate to support the common view that there has been an acceleration in the new skilled-biased technologies. Second, beginning around 1970, there has been a decline in the absolute level of the efficiency of unskilled labor, implying that the decline has played a significant role in the overall productivity slowdown and the substantial widening in the US wage structure.