Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
This paper offers some new estimates of the contribution of learning to the rapid increases in labor productivity observed in the construction of Liberty ships during World War II. The study exploits new data on physical capital investment and vessel quality constructed from contemporary records held at the National Archives. Estimates of the rate of learning are shown to be sensitive to the inclusion of the new capital data, and data on vessel quality provide evidence that part of the measured productivity increases were secured at the expense of quality.