Score contribution per author:
α: calibrated so average coauthorship-adjusted count equals average raw count
Short-term increasing returns to production factors are usually found in empirical studies. We argue they can be due to omitted variables, particularly the intensity of factor utilization. Thanks to original French firm-level data (1992–2008), we show how increasing returns to scale disappear when working time, capacity utilization rate, and, particularly, capital operating time are introduced in the production function. © 2015 The President and Fellows of Harvard College and the Massachusetts Institute of Technology