Multiscale impact of researcher mobility

Abstract

<jats:p>International mobility facilitates the exchange of scientific, institutional and cultural knowledge. Yet whether globalization and advances in virtual communication technologies have altered the impact of researcher mobility is a relevant and open question that we address by analysing a broad international set of 26 170 physicists from 1980 to 2009, focusing on the 10-year period centred around each mobility event to assess the impact of mobility on research outcomes. We account for secular globalization trends by splitting the analysis into three periods, measuring for each period the effect of mobility on researchers' citation impact, research topic diversity, collaboration networks and geographical coordination. In order to identify causal effects we leverage statistical matching methods that pair mobile researchers with non-mobile researchers that are similar in research profile attributes prior the mobility event. We find that mobile researchers gain up to a 17% increase in citations relative to their non-mobile counterparts, which can be explained by the simultaneous increase in their diversity of co-authors, topics and geographical coordination in the period immediately following migration. Nevertheless, we also observe that researcher's completely curtail prior collaborations with their source country in 11% of the cross-border mobility events. As such, these individual-level perturbations fuel multiscale churning in scientific networks, e.g. rewiring the connectivity of individuals and ideas and affecting international integration. Together these results provide additional clarity on the complex relationship between human capital mobility and the dynamics of social capital investment, with implications for immigration and national innovation system policy.</jats:p>

Methods to Account for Citation Inflation in Research Evaluation

“…(2). In order to demonstrate the utility of this deflator method in data-driven research, we refer the reader to three recent studies focusing on various units of analysis: individual careers (Petersen et al, 2014a;Petersen, 2018b) and individual publications (Parolo et al, 2015). As such, the contribution of the analysis reported here is to delineate the steps needed to obtain a generic deflator index D a (t) defined in Eq.…”

Increasing trend of scientists to switch between topics

“…The increased availability of large data sets that capture research activities creates an unprecedented opportunity to explore the dynamical patterns of scientific production and reward using state-of-the-art mathematical and computational tools 6–8 . Apart from the early works aiming at evaluating scientific impact with scientists’ citations 9 , h -index 10 , and related variants 11 , there is a recent wave of studies focusing on quantifying and modeling the evolution of research creativity throughout scientists’ careers 12–19 . Scientists’ cumulative production measured by the number of papers has been shown to exhibit persistent growth with time 12 , which is associated with the well-known Matthew effect 20 .…”

Cities and countries in the global scientist mobility network

“…Scientists are highly mobile professionals, especially in the early phase of their careers. The tendency to move has been observed in the past (Cardwell 1972;Mokyr 2016), but the size of the phenomenon has drastically increased over the years in a globalized market for high-skill labour (Culotta 2017;Geuna 2015;OECD 2017). Modern economies require a highly skilled labour force to maintain their competitive advantage and grow (Chambers et al 1998;Solimano 2008;Ozden and Rapoport 2018;Zucker and Darby 2007).…”