Persistency and Uncertainty Across the Academic Career

Recent shifts in the business structure of universities and a bottleneck in the supply of tenure track positions are two issues that threaten to change the longstanding patronage system in academia and affect the overall potential of science. The shift away from long term towards short term contracts necessitates that the employment review process account for coauthorship factors and the coexistence of cumulative advantage and uncertainty in the annual production ni(t) of a given scientist i. Here we analyze the longitudinal publication rate ni(t) on the 1-year time scale for 300 physicists i = 1...300 and show that the productivity of many physicists accelerates, Ni(t) ≈ Aiti , with αi > 1, reflecting the benefits of learning and collaboration spillovers which constitute a cumulative advantage. We find that the variance in production scales with “collaboration radius” size Si as σ i ∼ S ψ i with 0.4 < ψ < 0.8. To compare intellectual labor with manual labor, we analyze in parallel two comprehensive sports leagues comprising 21,156 careers. We use a preferential growth model to gain insight into the relation between career persistency and career uncertainty. This model shows that excessive emphasis on nonstop production, a consequence of short-term contract systems, results in a significant number of “sudden death” careers that terminate due to unavoidable negative production shocks. Altogether, our results indicate that short-term contracts may increase the strength of “rich-get-richer” mechanisms in competitive professions and hinder the upward mobility of young scientists. 1 Wednesday, February 29, 2012 Preferential Capture with Appraisal 7 B. Initial Condition The initial weight at the beginning of the simulation is wi(t = 0) ≡ nc for each agent i with nc ≡ 1. The value nc > 0 ensures that competitors begin with a non-zero production potential, and corresponds to a homogenous system where all agents begin with the same production capacity. Hence, we do not analyze the more complicated model wherein external factors (i.e. collaboration factors) can result in a heterogeneous production capacity across scientists. By construction, each agent begins with one unit of achievement ni(t = 1) ≡ 1.