Abstract This study offers a unique lens on the patterns, productivity, and impact of researcher mobility at a US research-intensive university. Bibliometric data for Washington State University (WSU) was extracted from Elsevier’s Scopus database and analyzed for the 10-year period from 2002 to 2012. We grouped researchers into four categories based on common patterns of movement into, within, and out of the USA: mobile (inflow, outflow, and transitory) versus non-mobile (stationary). We compared the research performances of these different groups using two normalized indicators: relative research productivity and the field-weighted citation impact of the researchers’ publications. Our analysis showed that 83% of active researchers at WSU were mobile during the 10-year period based on their having both publications affiliated with WSU and publications affiliated with at least one other institution. The publications of mobile researchers had higher impact compared to non-mobile researchers. Additionally, WSU researchers who primarily moved between other US-based institutions produced publications with higher impact compared to those of internationally mobile researchers, though the latter group was more prolific. Transitory researchers—those spending less than 2 years at either WSU or another institution—comprised the largest sub-group of mobile researchers at 59%. The results of this study offer additional evidence about the value to US universities of researcher mobility and greater research collaborations with both domestic and international partners. 1. Introduction To produce and disseminate new knowledge and discoveries, universities bring together a complex network of researchers, comprising professors, visiting scholars, fellows, technicians, staff, and students, who represent a wide range of ranks and disciplines. As a critical player in the overall research enterprise in a country, universities largely depend on government and public funding to support research and development activities particularly in science and technology. In the USA, a study by the National Research Council of the National Academies entitled ‘Furthering America’s Research Enterprise’ recognized the three critical pillars of the research system as ‘a talented and interconnected workforce, adequate and dependable resources, and world class basic research’ (Celeste, Griswold and Straf 2014). The movement of researchers, particularly students and trainees from developing countries to countries with more developed research infrastructure and resources, such as the USA, has previously been associated with the concepts of ‘brain drain’ and ‘brain gain’, and in terms of losers and winners (Ioannidis 2004; Bekhradnia and Sastry 2005; Tritah 2008; Ackers and Gill 2008; Plume 2012). Of five countries assessed by bibliometric analytics, the USA had the highest total number of researchers but the lowest degree of outward international movement of researchers compared to the United Kingdom, Germany, Italy, and the Netherlands (Moed et al. 2013). With increasing opportunities around the globe and increasing return of researchers to their institutions and/or countries of origin, ‘brain circulation’ is more commonly viewed as beneficial to all involved players (Cao 1996; Saxenian, 2002; Saxenian 2007; Jonkers and Tijssen 2008; Baruffaldi and Landoni 2016) with nations serving as ‘loci in a dynamic system of human capital flows’ (Johnson and Regets 1998). Although an institution may lose some of its best research talent to other institutions, for example, at the conclusion of graduate training, many researchers retain collaborative ties, return for short- and long-term visits, and serve as conduits transferring knowledge and other intellectual resources between institutions and countries (Scellato et al. 2012; Murakami 2013; Fernández-Zubieta and Lawson 2015). Hence, researcher mobility is now presented as a useful mechanism to encourage excellence in research systems, knowledge transfer, and deployment and networking (Cañibano, Otamendi, and Andújar 2008). These benefits of researcher mobility are widely recognized in national policies especially in Europe, e.g. European 2020 Strategy, and are attracting increased amounts of public funding (Cañibano, Otamendi, and Andújar 2008; Nordforsk 2014). Increased interest in researcher mobility has triggered efforts to understand the phenomenon of researcher mobility (Cox and Verbeek 2008; Auriol 2010; Aksnes et al. 2013; Appelt et al. 2015). Previous studies on the movement of researchers between institutions and countries have largely analyzed the broad social, economic, and political implications of mobility, particularly in the sciences (Vidal 1998; De Filippo et al. 2009; Franzoni et al. 2012; Van Noorden 2012; Gibson and McKenzie 2012; Science Europe and Elsevier 2013; Sun 2013), using analyses of census and migration data, curriculum vitae, researcher surveys, or a combination of these approaches (Johnson and Regets 1998; Dietz et al. 2000; Fontes 2007; Canibano 2008; Marceau 2008; Auriol 2010). Recently, researcher mobility and correlation to scholarly performance have been examined using publications and citation data but these studies have largely focused at the country level (Plume 2011; Conchi and Michels 2014; Schiller and Cordes 2016) and on emerging universities in developing economies (Salmi 2012). In 2013, Science Europe and Elsevier released a report Comparative Benchmarking of European and U.S. Research Collaboration and Researcher Mobility that provided a comparative view of European and US researcher mobility. This report analyzed the scholarly output and citation impact of different types of researchers, those who moved (between either European countries or US states) and those who did not. Aside from this report, comparative analyses of research performance associated with researcher mobility remains relatively under-studied in a solely US context. The purpose of this study is to add to the knowledge base on researcher mobility at the institutional level by using Washington State University (WSU) as a case study and using bibliometric approaches to understand the phenomenon of researcher mobility. The objectives of the study were twofold: (1) compare the scholarly output and academic impact of mobile researchers and non-mobile researchers; and (2) determine how different categories of researchers (based on mobility) contributed to the aggregate scholarly impact and research performance during the 10-year period. The study produced three important findings: (1) Active WSU researchers were very mobile during 2002–12, mostly at the domestic level with movement to other US institutions; (2) researchers who were internationally mobile produced more publications per year than did domestically mobile researchers; however, the citation impact of publications by the latter group was higher than that of the former group, although both groups showed higher field-weighted citation impact (FWCI) than the world average and WSU average; and (3) transitory researchers—those spending less than 2 years at an institution—comprised more than half of all active researchers; as a group, these researchers also produced publications with a higher FWCI than both the world and WSU average. These results are relevant for policymaking, especially in the selection and recruitment of researchers, indicator development on research performance, and cultivation of collaborations relevant to the US research enterprise. 2. Method There are over 4,000 public and private institutions of higher education in the USA; according to the Carnegie Classification of Institutions in Higher EducationTM, approximately 200 are responsible for over half of basic and early-stage applied research in the USA, produce graduates at the doctoral as well as bachelor and master levels, and contribute in many and diverse local, regional, national, and global ways (National Science Board 2012; American Academy of Arts and Sciences 2015). Of all accredited US institutions of higher education within the US National Center for Education Statistics Integrated Postsecondary Education Data System, WSU is classified by Carnegie as an R1 doctoral-highest research activity university. Using Elsevier’s Scopus bibliographic database, which is currently the largest abstract and citation repository of peer-reviewed literature in disciplines ranging from science and technology to arts and humanities, our study identified and analyzed more than 180,000 publications associated with 8,000 researchers having at least one publication (article, conference proceeding, or review) with WSU as author affiliation for the 10-year period from 2002 to 2012. Affiliation with WSU included all campuses and stations of the university, totaling eight main institution affiliation profiles in the Scopus database. Author profiles associated with the 8,000 researchers were created, including information on authors’ professional affiliations, publication history, and citation statistics within the 10-year period of this study. Authors listed addresses in their published articles were used as a proxy for their location and affiliation. To track researcher mobility and determine whether an author had moved domestically (movement between WSU and other US institutions) or internationally (movement between WSU and at least one international institution), we defined an author’s ‘original institution’ as the institutional affiliation listed on that author’s first publication within the 2002–12 period. However, the geographical location of the author as collected from Scopus is not necessarily indicative of the author’s nationality, country of birth, or permanent residence. Moreover, this approach does not distinguish between the level or rank of an individual’s position at that ‘original institution’. All authors with at least one publication affiliated with WSU over the 10-year period were considered as researchers (n = 8,124), but a large proportion of those authors produced only one or relatively few articles. Previous studies have considered researchers with low publication output as those who had either left the research system or were not career researchers (Plume 2012). This study adopted a similar approach, applying a productivity filter that limited the analysis to ‘active researchers’ (n = 3,616). ‘Active researchers’ were defined as researchers who had (a) at least one publication indicating affiliation with WSU produced in the most recent 5-year period of the data set (2008–12) and more than 10 publications over the complete timeframe of the analysis for 2002–12; or (b) produced more than three publications for the last 5-year period (2008–12). We used the model adopted from Moed et al. (2013) and methodology in Plume (2011), Elsevier (2013), and Blom et al. (2016) to track researchers based on their mobility categories (non-mobile or stationary versus mobile reflecting inflow, outflow, or transitory) and institutional type (US domestic versus international institution). Figure 1 presents the researcher mobility model that was adopted for this study. Figure 1. View largeDownload slide Researcher Mobility Model and categories used in analyzing WSU researcher mobility for 2002-2012. Figure 1. View largeDownload slide Researcher Mobility Model and categories used in analyzing WSU researcher mobility for 2002-2012. Stationary researchers were individuals who had published with affiliation to only WSU; based on their publication history from 2002 to 2012, there was no evidence that they had spent considerable time doing research away from WSU. Mobility was defined as listing affiliations (across a researcher’s total publications) to at least two different institutions during the 10-year period of study, i.e. WSU and another US institution (domestic mobility) or WSU and a non-US institution (international mobility). Consistent with previous mobility studies (Crawford et al. 1993; Plume 2012; Elsevier 2013; Moed et al. 2013), mobility was further sub-categorized based on the length of the stays at various institutions: transitory or short-term stays of less than 2 years versus long-term stays. The set of WSU researchers counted toward domestic and international mobility included some overlap since researchers may have moved to and published with a US institution and also have moved to and published with a foreign institution during the 10-year period. For example, a researcher who had the following institutional trajectory, WSU > International> Domestic> WSU would be categorized as either a ‘Transitory’ or a ‘Return to WSU Inflow’ in either domestic or international mobility, depending on how long (less or more than 2 years) that researcher spent at each non-WSU institution. Table 1 provides additional description on mobility categories. Table 1. Categories of WSU active researchers used in the researcher mobility model Category Subcategory Description 1. Non-mobile stationary Researchers who only published with WSU affiliation and without any apparent mobility to other institutions/countries based on their publication record 2. Mobile (1) Total inflow a. Inflow (permanent) Researchers who first published with a non-WSU institution, came to and published with WSU, and did not leave for the rest of the study timeframe b. Return to WSU inflow Researchers who first published while at WSU, went to another institution and/or country for 2 or more years (long term), and then returned to and published with WSU affiliation (2) Total outflow a. Outflow (permanent) Researchers who first published while at WSU, and then left for another institution and/or country and published with non-WSU affiliation. They did not return to WSU b. Return to non-WSU outflow Researchers who first published with a non-WSU institution, came to WSU for 2 or more years (long term) and published with WSU affiliation, and then left for another institution and/or country and published with non-WSU affiliation (3) Total transitory Researchers who spent less than 2 years (short-term stay) and published at WSU or a non-WSU institution a. Mainly WSU Publications (>50%) were predominantly affiliated with WSU b. Mainly non-WSU Publications (50%) were predominantly affiliated with non-WSU institution Category Subcategory Description 1. Non-mobile stationary Researchers who only published with WSU affiliation and without any apparent mobility to other institutions/countries based on their publication record 2. Mobile (1) Total inflow a. Inflow (permanent) Researchers who first published with a non-WSU institution, came to and published with WSU, and did not leave for the rest of the study timeframe b. Return to WSU inflow Researchers who first published while at WSU, went to another institution and/or country for 2 or more years (long term), and then returned to and published with WSU affiliation (2) Total outflow a. Outflow (permanent) Researchers who first published while at WSU, and then left for another institution and/or country and published with non-WSU affiliation. They did not return to WSU b. Return to non-WSU outflow Researchers who first published with a non-WSU institution, came to WSU for 2 or more years (long term) and published with WSU affiliation, and then left for another institution and/or country and published with non-WSU affiliation (3) Total transitory Researchers who spent less than 2 years (short-term stay) and published at WSU or a non-WSU institution a. Mainly WSU Publications (>50%) were predominantly affiliated with WSU b. Mainly non-WSU Publications (50%) were predominantly affiliated with non-WSU institution Two normalized indicators were used in analyzing each of the researcher groups: Relative productivity represents the number of papers published per year (PPY) since the first appearance of each researcher as an author in the Scopus database during the period 2002–12, relative to all active researchers at WSU for the 10-year period. This measure normalizes for career length, allowing comparison of productivity across different groups, e.g. early career versus senior established researchers. This indicator was calculated based on an author’s entire output of articles, including those with WSU and non-WSU affiliations. For example, if active researchers achieved a relative productivity score of 1.28, that indicates that that category of researchers published 28% more papers per year than did all active WSU researchers. Field-weighted Citation Impact represents a measure of research impact based on citations and normalizes for differences in citation activity by subject field, article type, and publication year in the entire Scopus database. For example, an FWCI of 1.80 indicates a citation impact that is 1.8 times the world average, or 80% above the world average.Weighted scores of each mobility group (mobile versus non-mobile and domestic versus international) were calculated for the two normalized indicators. Relative productivity scores were weighted by ratios of the total number of papers and total occurrences of authors for 2002–12 to number of PPY. FWCI scores were weighted by ratios of FWCI to number of papers for 2002–12. All calculations were based on ‘whole counting’ of publications, i.e. all authors received full credit as has been applied in other studies (Aksnes et al. 2012; Plume 2012). 3. Results Based on 8,124 authors affiliated with WSU from 2002 to 2012, 3,616 active researchers were identified for the researcher mobility analysis. The average PPY was 5.21, and the FWCI of publications from the active researchers was 48% higher than the world average of 1.0 based on the entire Scopus database of publications (Table 2); in comparison, the average FWCI of the group of ‘non-active’ WSU researchers was 1.43 for the study period. For reference, the FWCI associated with all WSU publications (e.g., an author explicitly lists WSU as an affiliation in that publication) from 2002 to 2012 was 1.40. Table 2. Distribution of WSU’s active researchers based on mobility and destination, 2002–12 Indicators Type of mobility Non-mobile Mobile Domestic International Number of active researchers 3,616 621 2,995 2,329 1,208 Relative productivity 1.00 0.48 1.09 1.19 1.72 FWCI 1.48 1.30 1.50 1.52 1.38 Indicators Type of mobility Non-mobile Mobile Domestic International Number of active researchers 3,616 621 2,995 2,329 1,208 Relative productivity 1.00 0.48 1.09 1.19 1.72 FWCI 1.48 1.30 1.50 1.52 1.38 3.1 Mobility of researchers Only 17% (621 of 3,616) of WSU active researchers who published during the 10-year period were classified as non-mobile or stationary because all of their publication records were only affiliated with WSU (Table 2). This non-mobile group of researchers had relatively low productivity at 0.48 and probably included a large proportion of early career researchers. Despite their lower productivity, the academic impact of these researchers (FWCI = 1.30) was above the world average of 1. The majority of active researchers were mobile (83%, 2,995 of 3,616), publishing with WSU and one or more non-WSU institutions during the 10-year period (Table 2). Overall, the group of mobile researchers was more productive and produced publications that were of higher citation impact than did the group of non-mobile researchers. Table 3 shows the bibliometric data and performance of WSU active researchers based on the researcher mobility model’s mobility categories. With regard to permanent inflow and outflow, 9% (315 of 3,616) of WSU active researchers ‘permanently’ moved to WSU (Inflow). This was balanced with about 8% (297 of 3,616) who ‘permanently’ moved out of the university (Outflow). Inflow researchers produced more publications per year (relative productivity 0.69 versus 0.55) and their output was more impactful (FWCI 1.63 versus 1.55) than that of the Outflow researchers. Table 3. Bibliometric data and performance of WSU active researchers for 2002–12 based on the researcher mobility model’s mobility categories, n = 3,616 Indicators Non-mobile Mobile Total inflow Total outflow Total transitory Stationary Inflow Return to WSU inflow Outflow Return to non-WSU outflow Transitory mainly WSU Transitory mainly non-WSU Number of researchers 621 315 56 297 193 591 1,543 Relative productivity 0.48 0.69 1.11 0.55 0.79 0.65 1.45 FWCI 1.3 1.63 1.27 1.55 1.49 1.42 1.47 Indicators Non-mobile Mobile Total inflow Total outflow Total transitory Stationary Inflow Return to WSU inflow Outflow Return to non-WSU outflow Transitory mainly WSU Transitory mainly non-WSU Number of researchers 621 315 56 297 193 591 1,543 Relative productivity 0.48 0.69 1.11 0.55 0.79 0.65 1.45 FWCI 1.3 1.63 1.27 1.55 1.49 1.42 1.47 Less than 2% (56 of 3,616) of active researchers were categorized as returnees—those who first published with WSU, moved out, and subsequently returned to WSU after more than 2 years at another institution (Return to WSU Inflow). In contrast, the ‘Return to non-WSU Outflow’ group of researchers, who first published with a non-WSU institution, then came to WSU for 2 or more years and subsequently left for another institution, was greater at 5.30%; however, the latter group was less productive than the ‘Return to WSU Inflow’ group. The citation impact of publications of the Outflow returnees (FWCI = 1.49) was slightly higher than that of all active researchers (FWCI = 1.48). WSU also attracted a large number of ‘transitory’ researchers, who represented more than half of all active researchers (59% or 2,134 of 3,616). This transitory group presumably largely comprised visiting scholars, fellows, and short-term students spending less than 2 years at the institution. Based on their publication records, this group was sub-classified as being primarily affiliated with WSU (16% or 591 of 3,616) or with a non-WSU institution (43% or 1,543 of 3,616). Both groups produced publications of higher citation impact than the world average (FWCI of 1.42 and 1.47, respectively). 3.2 Domestic versus international mobility We analyzed the movement of WSU researchers between domestic and international institutions within the context of differences in relative productivity and impact. During 2002–12, 64% (2,329 of 3,616) of the total pool of WSU active researchers had published at least once with another US institution, while only 33% (1,208 of 3,616) had shown international mobility and published at least once with an affiliation to a foreign institution (Table 2). Of all active researchers who left WSU permanently for another institution (Outflow group n = 297, Table 3), 78% (231 of 297) moved to another US institution (Table 2). Additionally, 74% (234 of 315) of researchers who moved permanently to WSU (Inflow group, Tables 2 and 3) were from another US institution. However, researchers who moved between WSU and another domestic institution produced fewer publications (relative productivity = 1.19) compared to researchers who moved between WSU and international institutions (relative productivity = 1.72). Domestically mobile researchers however had publications with higher impact (FWCI = 1.52) than internationally mobile researchers (FWCI = 1.38). 3.3 Impact of domestic mobility Table 4 presents the researcher mobility analysis for domestically mobile researchers who moved between WSU and other US institutions. For the entire 10-year period, an almost balanced proportion of domestic researchers moved into WSU (Total Inflow 283 of 2,329) and out of WSU (Total Outflow 330 of 2,329). Both groups had lower productivity compared to the output of all active WSU researchers (0.79 and 0.61, respectively). Notably, the impact of both groups was very high with FWCI scores of 50–60% above the world average (compared to the FWCI of all active WSU researchers of 1.48, or 48% above the world average). Table 4. Bibliometric data of WSU active researchers for 2002–12 based on the researcher mobility model’s domestic mobility categories, n = 2,329 Indicators Domestic mobility Total inflow Total outflow Total transitory Inflow Return to WSU inflow Outflow Return to non-WSU outflow Transitory mainly WSU Transitory mainly non-WSU Number of researchers 234 49 231 99 491 1,225 Relative productivity 0.71 1.19 0.56 0.71 0.68 1.63 FWCI 1.62 1.27 1.65 1.59 1.42 1.48 Indicators Domestic mobility Total inflow Total outflow Total transitory Inflow Return to WSU inflow Outflow Return to non-WSU outflow Transitory mainly WSU Transitory mainly non-WSU Number of researchers 234 49 231 99 491 1,225 Relative productivity 0.71 1.19 0.56 0.71 0.68 1.63 FWCI 1.62 1.27 1.65 1.59 1.42 1.48 In terms of domestic returnees, 2% (49 of 2,329) of all domestically mobile WSU researchers classified as ‘Return to WSU Inflow’ while 4% (99 of 2,329) classified as ‘Return to non-WSU Outflow’. The ‘Return to non-WSU’ outflow researchers produced fewer publications on average (relative productivity = 0.71) than the ‘Return to WSU inflow’ group who were more productive (relative productivity = 1.19). Both groups achieved citation impacts higher than the world average with FWCI scores of 1.27 and 1.59, respectively. While total number of researchers in the domestic returnee groups and their output was small, the citation impact of their publications was high. More than 30% (34%, 1,225 of 2,329) of domestically mobile researchers belonged to the group of short-term, transitory researchers who had the majority of their output affiliated with non-WSU institutions; these researchers displayed high productivity (FWCI = 1.63). Transitory researchers who had the majority of their output affiliated with WSU were less productive (relative productivity = 0.68). Both domestically mobile, transitory groups produced publications with high impact (FWCI = 1.42 and 1.48) well above the world average but comparable to the impact of the total pool of all active WSU researchers (FWCI = 1.48). 3.4 Impact of international mobility Table 5 presents the researcher mobility analysis for internationally mobile researchers who moved between WSU and a foreign institution. For the entire period of analysis, there were relatively few international researchers moving permanently into WSU (Inflow 81 of 1,208) or out of WSU (Outflow 66 of 1,208). Both groups had significantly lower productivity (0.63 and 0.53, respectively) than the average for WSU. However, the citation impact of publications from both these groups, especially for Inflow researchers (FWCI = 1.65), was higher than the world average and the average for all WSU active researchers (FWCI = 1.48). Table 5. Bibliometric data of WSU active researchers for 2002–12 based on the researcher mobility model’s international mobility categories, n = 1,208 Indicators International mobility Total inflow Total outflow Total transitory Inflow Return to WSU inflow Outflow Return to non-WSU outflow Transitory mainly WSU Transitory mainly non-WSU Number of researchers 81 26 66 34 150 851 Relative productivity 0.63 1.4 0.53 0.98 0.75 2.1 FWCI 1.65 1.1 1.16 1.14 1.54 1.39 Indicators International mobility Total inflow Total outflow Total transitory Inflow Return to WSU inflow Outflow Return to non-WSU outflow Transitory mainly WSU Transitory mainly non-WSU Number of researchers 81 26 66 34 150 851 Relative productivity 0.63 1.4 0.53 0.98 0.75 2.1 FWCI 1.65 1.1 1.16 1.14 1.54 1.39 In terms of international returnees who engaged in longer stays of 2 or more years at an institution, the numbers were relatively low at 26 for the ‘Return to WSU Inflow’ group and 34 for the ‘Return to non-WSU Outflow’ group out of the total pool of 1,208 internationally mobile researchers (Tables 2 and 5). Seventy percent (851 of 1,208) of internationally mobile researchers belonged to the group of short-term transitory researchers, with the majority of their publication output affiliated with a foreign institution; this group was also remarkably productive (relative productivity 2.1). Transitory researchers with the majority of their publications affiliated with WSU only comprised 12% (150 of 1,208) of all internationally mobile researchers. As shown in Table 4, both transitory groups produced publications with impact higher (FWCI = 1.54 and 1.39) than the world average. 4. Discussion The results of this study indicated that WSU researchers who actively published were very mobile during the 10-year period of study, and this mobility was mostly at the domestic level with other US institutions. Researchers who were internationally mobile produced more publications than domestically mobile researchers. While both groups achieved a higher FWCI than the world average, the publications of domestically mobile researchers received higher citation impact than internationally mobile researchers. Transitory researchers (those spending less than 2 years at an institution) represented more than half of all active WSU researchers and, as a group, produced publications with higher citation impact than the world and WSU average. Plume (2011) noted that countries with highly developed research infrastructures tended to have a large percentage of transitory researchers and the productivity of these researchers was generally high. The high level of mobility of active researchers and the quantity and FWCI of their publications are consistent with other studies that recognized the gains in productivity and citation rates by mobile scholars (Aksnes et al. 2013; Elsevier 2013; Moed et al. 2013; Geuna 2015). Institutions benefit from high quantity and quality of publications in various ways including higher university rankings, and better recognition in peer-reviews, student applications and other informal reputational gains (Aksnes, Schneider, and Gunnarsson 2012; Avralev and Efimova 2013; Kim and Bak 2016; Turko et al. 2016). Beyond institutional benefit, mobility was also noted as important in advancing academic careers and as a characteristic of researchers in countries with developed research infrastructures based on results for the UK (Plume 2011). Other studies on researcher mobility across a range of countries have found that American researchers are generally less mobile than their international counterparts. The report published by Science Europe and Elsevier Analytical Services (2013) classified the majority of US researchers as stationary, based on publication records reflecting only affiliations within the USA; this study did not distinguish between domestic versus international mobility, and hence may have understated the level of geographic mobility among US researchers. The findings of this study for WSU indicate a high level of active researcher mobility and the potential value of more institutional-level assessments to monitor researcher mobility at other US universities. The higher proportion of domestically mobile researchers corroborates the argument by Deville et al. (2014) that geography affects career movement decisions and can be approximated with a power law distribution; the authors suggest that most movements are local, and people at elite institutions are more likely to move to another elite institution. The WSU analysis also showed that internationally mobile researchers, whether short-term or long-term, provided benefits to WSU in the form of scholarly output with higher impact than the world average for 2002–12. This group of researchers, like the domestically mobile researchers, made significant contributions to the overall research profile of the university. Similarly, Levin and Stephan (1999) and No and Walsh (2010) have complementary observations on the importance of foreign-born talent and as a source of strength to enhancing the US knowledge-based economy. Their relatively lower level of productivity in publication numbers may be attributed to the lag time required to adjust to a new institution and culture, establish their programs, and obtain resources; further studies could examine the productivity of this group over a longer time frame. These internationally mobile researchers have the potential to enhance diversity while conducting scholarly activities that result in impactful publications benefiting both WSU and their originating institutions and countries. Several recent studies, however, have shown changing trends in the preference of international researchers to return to their countries of origin or to seek other competitive positions around the globe (Jonkers and Tijssen 2008; Baruffaldi and Landoni 2016). Kim et al. (2011) and Lu, Miller, and Newman (2013) have indicated that the process of hiring international faculty at US institutions is sometimes considered to be cumbersome—from complying with national regulations and requirements for hiring foreign workers to preparing them to deal with cultural differences and integrating them into the university system—all entailing a larger investment of time, money, and effort versus recruiting students, short-term scholars, or exchange visitors. As observed with domestically transitory researchers, internationally transitory researchers who produce impactful publications likely included senior researchers who came to WSU presumably as visiting and exchange scholars. Overall, WSU is effective as an institution in attracting short-term ‘transitory’ researchers who likely represent visiting and non-tenure track scholars and as a group, represented more than half of the active researchers. These researchers are generally ambitious to establish their publication record with high caliber research that might position them for academic as well as industry and business career opportunities (Howell et al. 2010). Because of the perceived and possible insecurity of their appointments in visiting and non-tenure-track positions, these researchers also exhibit high mobility in efforts to pursue new opportunities at other institutions that may offer the security of tenure, a wider network of professional colleagues and mentors, and more attractive resources and facilities (Salaman and Kumar 2012). These transitory researchers despite not being retained at WSU are part of the growing research network of the university and can serve as collaborators for future research partnerships between WSU and their current institution. 5. Conclusion Using a combined approach of bibliometric analyses, select proxy measures, and the researcher mobility model adopted from Moed et al. (2013), this case study on WSU provided an institutional level assessment of researcher mobility at a research-intensive US university. As a critical component of the research and higher education landscape, research-intensive public universities are facing several challenges, and the caliber and productivity of an institution’s human capital in research is therefore of increasing significance. The profile of mobility within context of publication productivity and the impact of their output offers one of several approaches for institutions to assess their overall research performance, composition of researchers, and strategies for enhancing both domestic and international collaborations. The results of this study affirmed earlier conclusions that mobile researchers generate publications with greater impact suggesting that institutions should continue to support and incentivize opportunities for mobility. Greater mobility was observed between WSU and other US institutions than with international institutions, and transitory researchers who stayed for less than 2 years at an institution dominated the composition of the active researcher pool for 2002–12. While universities generally provide more incentives and resources for their resident researchers, the productivity and impact of the publication output from transitory researchers weighs significantly in the overall research impact for the institution and this group deserves greater analysis. Despite the high mobility of active researchers, for the 10-year period of analysis from 2002 to 2012, WSU was able to recruit and retain slightly more researchers, who in turn produced higher impact and quantity of publication output. In future studies, the detailed composition of the inflow and outflow researchers with regard to personnel type (i.e. faculty, student, visiting scholar, or other staff status) would provide further granularity in formulating institutional strategy and policy decisions. Overall, our results shed light on the importance of mobility to research performance and academic impact of researchers, two important metrics for research-intensive and global institutions. Our findings are potentially relevant for institutional policy making especially in the selection and recruitment of researchers, domestic or international, indicator and metrics development on research performance and partnerships, and design of modalities and development of appropriate incentives for promoting mobility among US researchers. As Plume (2012) and others have previously indicated, the use of bibliometric analyses has several caveats including the accuracy of institutional affiliation reported on publications and differences in publication rates and project type and duration in different fields. Previous studies have also documented that research collaboration and knowledge exchange are facilitated by geographic proximity as well as economic, socio-political, language, institutional ranking, and other researcher attributes such as seniority, reputation, and productivity (Katz 1994; Ponds et al. 2007). At most universities, one of the criteria for promotion of professors typically requires evidence of international recognition and collaboration but this is not necessarily associated with either short- or long-term stays at a foreign institution or indication of that visit by inclusion of that affiliation on subsequent joint publications. Inward mobility of international talent also generates and strengthens collaborations and connections to the global scientific network. The desire and capacity of international researchers to maximize their experiences and produce more scholarly output while at a visiting university also could be further leveraged and supported. Foreign-born talent has contributed significantly to the intellectual capacity of US universities representing 27% of those with doctoral degrees conducting R&D in science and engineering fields in 1993 and increasing to 42% in 2013 (National Science Board 2016). This study also showed that the group of domestically mobile researchers generated publications of higher research impact albeit of lower number compared to internationally mobile researchers. As noted in the 2007 report of the US National Science Foundation’s Division of Science Resource Statistics, the total number of US articles began to decline in the 1990s; this trend was noted as an increasing commitment to quality as well as interdisciplinary and international collaborations (Bell et al. 2007). While this study was specific to one US public research-intensive university, the findings may serve as an important reference for other US and international universities to replicate the analysis, conduct their own assessment, and better understand the phenomenon of researcher mobility in their own setting. Further research could focus on institutional analysis of mobility at the level of personnel, discipline, or research area as well as analysis of specific institutions as well as countries to and from which researchers move the most, and strategic approaches to incentivize and further domestic as well as international partnerships. Additionally, there are limitations to the use of publication data for assessing the impact of researcher mobility particularly for internationally mobile researchers; in addition to bibliometric analyses, other metrics could also be incorporated for a broader assessment and for benchmarking comparisons including proposals submitted and awarded, activities other than publications (e.g. creative endeavors), awards and honors associated with international collaborations, and other indicators. Acknowledgments Many thanks to Judith Kamalski, Jeroen Baas, M’hamed el Aisati, and the Analytical Services team at Elsevier Research Intelligence for assistance with the data and indicators. Funding This work was part of a project supported by the National Science Foundation Award Number NCSE-1324474. Preliminary results of this study were presented at the 2016 annual meeting of the American Association for the Advancement of Science, Washington, DC. References Ackers L., Gill B. ( 2008) Moving People and Knowledge. In Scientific Mobility in an Enlarging European Union . Cheltenham. Edward Elgar Publishing Ltd. Google Scholar CrossRef Search ADS Aksnes D., Schneider J., Gunnarsson M. ( 2012) ‘Ranking National Research Systems by Citation Indicators. A Comparative Analysis Using Whole and Fractionalized Counting Methods’, Journal of Informetrics , 6: 36– 43. Google Scholar CrossRef Search ADS Aksnes D. et al. ( 2013) ‘Are mobile Researchers More Productive and Cited than Non-Mobile Researchers; A Large-Scale Study of Norwegian Scientists’, Reseaech Evaluation , 22: 215– 23. Google Scholar CrossRef Search ADS American Academy of Arts and Sciences. ( 2015) Public Research Universities: Why They Matter . Cambridge, MA: The Lincoln Project: Excellence and Access in Public Higher Education. Appelt S., van Beuzekom B., Galindo- Rueda, de Pinho R. ( 2015). Which Factors Influence the International Mobility of Research Scientists? Paris, France: OECD Publishing. Auriol L. ( 2010) ‘Careers of Doctorate Holders: Employment and Mobility Patterns’, OECD Science, Technology, and Industry Working Papers. Paris, France: OECD Publishing. Avralev N., Efimova I. ( 2013) ‘University Rankings as a Tool to Enhance Competitiveness, Clustering and Transnational Governnance of Higher Education in the Context of Globalization’, Middle East Journal of Scientific Research , 16/ 3: 357– 61. Baruffaldi S. H., Landoni P. ( 2016) ‘Mobility Intentions of Foreign Researchers: The Role of Non-economic Motivations’, Industry and Innovation , 23/ 1: 87– 111. Google Scholar CrossRef Search ADS Bekhradnia B., Sastry T. ( 2005) Migration of Academic Staff to and from the UK . London: Higher Education Policy Institute. Bell R. K., Hill D., Lehming R. F. ( 2007) ‘The Changing Research and Publication Environment in American Research Universities’, Working Paper SRS 07-204. Arlington: National Science Foundation, Division of Science Resources Statistics. Arlington, VA: National Science Foundation, Division of Science Resources Statistic. Blom A., Lan G., Adil M. ( 2016) Sub-Saharan African Science, Technology, Engineering, and Mathematics Research. A decade of development . Washington, DC: International Bank for Reconstruction and Develpment/World Bank. Canibano C. ( 2008) ‘Measuring and Assessing Researcher Mobility from CV Analysis: The Case of the Ramon y Cajal Programme in Spain’, Research Evaluation , 17/ 1: 17– 31. Google Scholar CrossRef Search ADS Cañibano C., Otamendi J., Andújar I. ( 2008). Measuring and Assessing Researcher Mobility from CV Analysis: The Case of the Ramon Y Cajal Programme in Spain. Research Evaluation , 17/ 1: 17– 31. Google Scholar CrossRef Search ADS Cao X. ( 1996) ‘Debating ‘Brain Drain’ in the Context of Globalisation’, Compare: A Journal of Comparative and International Education , 26/ 3: 269– 84. Google Scholar CrossRef Search ADS Celeste R. F., Griswold A., Straf M. L. ( 2014) ‘Furthering America's Research Enterprise’, in Committee on Assessing the Value of Research in Advancing National Goals . Division of Behavioral and Social Sciences and Education, National Research Council. Conchi S., Michels C. ( 2014) ‘Scientific Mobility: An analysis of Germany, Austria, France, and Great Britain’, Fraunhofer ISI Discussion Papers. Innovation Systems and Policy Analysis. Karlsruhe, Germany: Fraunhofer Institute for Systems and Innovation Research ISI. Cox, D., and Verbeek, A. (2008). Evidence on the Main Factors Inhibiting Mobility and Career Development of Researchers. Brussels: European Commission. Crawford E., Shinn T., Sorlin S. ( 1993) ‘Denationalizing Science’, in Crawford E., Shinn T., Sorlin S., The Nationalization and Denationationalization of the Sciences: An Introductory Essay . Dordrecht: Kluwer. De Filippo F., Casado E., Gomez I. ( 2009) ‘Quantitative and Qualitative Approaches to the Study of Mobility and Scientific Performance: A Case Study of a Spanish University’, Research Evaluation , 18/ 3: 191– 200. Google Scholar CrossRef Search ADS Deville P. et al. ( 2014) ‘Career on the Move: Geography, Stratification, and Scientific’, Scientific Reports , 4: 4770. Google Scholar CrossRef Search ADS PubMed Dietz J. S. et al. ( 2000) ‘Using the Curriculum Vitae to Study the Career Paths of Scientists and Engineers: An Exporatory Assessment’, Scientometrics , 49/ 3: 419– 42. Google Scholar CrossRef Search ADS Elsevier ( 2013) ‘International Comparative Performance of the UK Research Base – 2013’, A report prepared by Elsevier for the UK’s Department of Business, Innovation and Skills. The Netherlands: Elsevier Analytical Services. Fernández-Zubieta A., Lawson C. ( 2015) ‘What Do We Know of the Mobility of Research Scientists and Impact on Scientific Production’, In Global Mobility of Research Scientists: The Economics of Who Goes Where and Why, pp. 1-33. San Diego, CA: Academic Press, Elsevier. Fontes M. ( 2007) ‘Scientific Mobility Policies: How Portuguese Scientists Envisage the Return Home’, Science and Public Policy , 34/ 4: 284– 98. Google Scholar CrossRef Search ADS Franzoni C. et al. ( 2012) ‘Patterns of International Mobility of Researchers: Evidence from the GlobSci Survey’, in International Schumpeter Society Conference . July 2012, Brisbane Australia. Geuna A. ( 2015) Global Mobility of Research Scientists: The Economics of Who Goes Where and Why . The Netherlands: Academic Press. Gibson J., McKenzie D. ( 2012) ‘The Economic Consequences of “Brain Drain” of the Best and the Brightest: Microeconomic Evidence from Five Countries’, The Economic Journal , 122/ 560: 339– 75. Google Scholar CrossRef Search ADS Howell L. et al. ( 2010) ‘Issues and Challenges of Non-Tenure Track Research Faculty: The UC Davis School of Medicine Experience’, Academic Medicine , 85/ 6: 1041– 7. Google Scholar CrossRef Search ADS PubMed Ioannidis J. ( 2004) ‘Global Estimates of High-Level Brain Drain and Deficit’, Journal of the Federation of American Societies for Experimental Biology , 18: 936– 9. Google Scholar CrossRef Search ADS Johnson J. M., Regets M. C. ( 1998) ‘International mobility of scientists and engineers to the United States—brain drain or brain circulation?’, National Science Foundation Issue Brief, 98– 316. Arlington, VA: National Science Foundation. Jonkers K., Tijssen R. ( 2008) ‘Chinese researchers returning home: Impacts of international mobility on research collaboration and scientific productivity’, Scientometrics , 77: 309– 33. Google Scholar CrossRef Search ADS Katz J. ( 1994) ‘Geographical proximity and scientific collaboration’, Scientometrics , 31/ 1: 31– 43. Google Scholar CrossRef Search ADS Kim D., Bak H.-J. ( 2016) ‘How Do Scientists Respond to Performance-Based Incentives? Evidence from South Korea’, International Public Management Journal , 31– 52. Kim D., Wolf-Wendel L., Twombly S. ( 2011) ‘International Faculty: Experiences of Academic Life and Productivity in U.S. Universities’, Journal of Higher Education , 82: 720– 47. Google Scholar CrossRef Search ADS Levin S., Stephan P. ( 1999) ‘Are the Foreign Born a Source of Strength for U.S. Science?’, Science , 29/ 85: 1213– 4. Google Scholar CrossRef Search ADS Lu M., Miller M., Newman R. ( 2013) ‘The Global Scholar: Challenges and Opportunities of Working with Transnational Faculty in Higher Education’, in Mukerji S., Tripathi P. (eds) Handbook of Research on Transnational Higher Education , pp. 1– 860. Hershey, PA: Information Science Reference (imprint of IGI Global). Marceau J. ( 2008) ‘Innovation Agents: The Inter-Country Mobility of Scientists and the Growth of Knowledge Hubs in Asia’, In: Proceedings of the DRUID 25th Celebration Conference, Copenhagen, Denmark, 17-20 June, 2008. Moed H., Aisati M., Plume A. ( 2013) ‘Studying Scientific Migration in Scopus’, Scientometrics , 94/ 3: 929– 42. Google Scholar CrossRef Search ADS Murakami Y. ( 2013) ‘Influences of Return Migration on International Collaborative Research Networks: Cases of Japanese Scientists Returning from the U.S’, The Journal of Technology Transfer , 39: 616– 34. Google Scholar CrossRef Search ADS National Science Board. ( 2012) Diminishing Funding and Rising Expectations: Trends and Challenges for Public Research Universities, A Companion to Science and Engineering Indicators. National Science Foundation NSB-12-45 . National Science Board. National Science Board. ( 2016) Science and Engineering Indicators. National Science Foundation NSB-2016-1 . National Science Board. No Y., Walsh J. ( 2010) ‘The Importance of Foreign-Born Talent for US Innovation’, Nature Biotechnology , 28: 289– 91. Google Scholar CrossRef Search ADS PubMed Nordforsk. ( 2014). Crossing Borders - Obstacles and Incentives to Researcher Mobility. Policy Paper , 3: 1– 142. Plume. ( 2011) International Comparative Performance of the UK Research Base . London: Elsevier. Plume A. ( 2012) ‘The Evolution of Brain Drain and its Measurement: Part II’, Research Trends , 3– 6. Ponds R., Van Oort F., Frenken K. ( 2007) ‘The Geographical and Institutional Proximity of Research Collaboration’, Papers in Regional Science , 86/ 3: 423– 43. Google Scholar CrossRef Search ADS Salaman M., Kumar P. ( 2012) ‘Maximizing the Value of Non-Tenure-Track Researchers at Research-Intensive Institutions’, Education Advisory Board Custom Research Brief , 1– 14. Salmi J. ( 2012) ‘Attracting Talent in a Global Academic World: How Emerging Research Universities Can Benefit from Brain Circulation’, Brain Circulation , 2/ 1. The Academic Executive Brief. Saxenian A. ( 2002) ‘Brain Circulation: How High-Skilled Immigration Makes Everyone Better Off’, Brookings Review , 20/ 1: 28– 31. Google Scholar CrossRef Search ADS Saxenian A. ( 2007) The New Argonauts: Regional Advantage in a Global Economy . Cambridge: Harvard University Press. Scellato G., Franzoni C., Stephan P. ( 2012) ‘Mobile Scientists and International Networks’, NBER Working Paper, pp. 1– 33. Cambridge, MA: National Bureau of Economic Research. Schiller D., Cordes A. ( 2016) ‘Measuring Researcher Mobility: A Comparison of Different Datasets and Methods with an Empirical Application of Micro-Data for the United STates and Germay’, OECD Blue SKy Forum 2016. <https://www.oecd.org/sti/062%20-%20Schiller-Cordes-Researcher-Mobility-final.pdf>. Science Europe and Elsevier. ( 2013) Comparative Benchmarking of European and U.S. Research Collaboration and Researcher Mobility . The Netherlands: Elsevier. Sun W. ( 2013) ‘The Productivity of Return Migrants: The Case of China's “Sea Turtles’, Journal of Migration , 2/ 1: 5. Google Scholar CrossRef Search ADS Tritah A. ( 2008) ‘The Brain Drain between Knowledge-Based Economies: The European Human Capital Outflow to the U.S.’, CEPII Working Paper. Turko T. et al. ( 2016) ‘Influence of the Program “5-top 100” on the Publication Activity of Russian Universities’, Scientometrics , 109/ 2: 769– 82. Google Scholar CrossRef Search ADS Van Noorden R. ( 2012) ‘Science on the Move’, Nature , 490: 327– 9. Vidal J. ( 1998) ‘The Effect of Emigration on Human Capital Formation’, Journal of Population Economics , 11/ 4: 589– 600. Google Scholar CrossRef Search ADS PubMed © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: email@example.com
Research Evaluation – Oxford University Press
Published: Jan 1, 2018
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.
All for just $49/month
Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.
Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.
It’s easy to organize your research with our built-in tools.
Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera