Is There a Skills Crisis?
The study examines available measures of skills and technology to shed light on the question of whether the growth of a skills gap can account for the growth in wage inequality and whether technology can be identified as playing a role in raising job skill requirements. In general, results indicate that skill requirements rose secularly between the early 1960s and late 1990s but show little evidence of the kind of acceleration that could explain the early 1980s surge in inequality.
Link
http://econwpa.wustl.edu/eps/mac/papers/0004/0004041.pdf