Mapping mobility - an introductory look at forms of and data on international student, academic and researcher mobility
"Wissenschaft weltoffen" uses a range of data sources on international student, academic and researcher mobility. When interpreting these data it must be borne in mind that there are several very different forms of student, academic and researcher mobility, and the collection of data on these is subject to very different conditions. It is for example far easier to analyse incoming Bildungsauslaender mobility into Germany than outgoing mobility of German students, as higher education statistics currently only cover the former. Evaluating the international mobility of academics and researchers is even more difficult, as Germany and many other countries keep only very incomplete official records of such mobility, and some countries (such as France) do not record it at all. The following pages therefore aim to provide an introductory explanation of the relevant types of student, academic and researcher mobility, the available data sources and their informative value.
A. Student mobility
Forms of mobility
When describing international student mobility, the two terms "degree mobility" and "credit mobility" are frequently used. According to the European mobility strategy ("Mobility for Better Learning"), degree mobility covers all study visits in the course of which a degree is gained abroad, while credit mobility refers to study-related visits abroad that lasted at least three months and/or in the course of which at least 15 ECTS credits were gained, but which formed part of a study programme leading to a degree in the student's home country. In addition to temporary study abroad this also includes visits for placements, language courses, study tours, project work and summer schools.
Following the distinction between credit and degree mobility, "Wissenschaft weltoffen" distinguishes between temporary study-related visits abroad (regardless of duration and number of credit points gained) and stays abroad with the aim of graduating abroad (degree-related international mobility). From this issue of "Wissenschaft weltoffen" onwards, both chapter B "Foreign students in Germany" and chapter C "German students abroad" will be structured on the basis of this distinction. It should be noted that due to the specific data collected it is more difficult to separate clearly between the two forms of mobility among outgoing students than among incoming students (see also the information in the following section).
Available data sources and data quality
Degree-related international mobility (DIM) of German students must be analysed based on the higher education statistics provided by the respective host countries, as these foreign students are not enrolled at a higher education institution in their respective country of origin. The Federal Statistical Office (Destatis) annually surveys the institutions responsible for education statistics in 30 important host countries of German students. The majority, but not all, of the reported students are most likely studying abroad with the intention to graduate there. For some countries the data also include Erasmus students and other students on temporary study visits. A helpful addition are therefore the data on German first-year students and graduates abroad collected by Destatis from the 2008 academic year onwards, which are however available for significantly fewer countries than the student numbers. In addition to the Destatis statistics, the international student statistics by UNESCO, OECD and the EU statistical office (Eurostat) can also be used to assess degree-related international mobility. These statistics are based on a joint survey, the "UOE data collection on education systems". Despite the common data basis, the three organisations have previously published different statistics on international student mobility, as they processed the underlying data in different ways. Starting with the reporting year 2013, the procedure previously employed by UNESCO has now been defined as the standard procedure for all three organisations. Compared to the Destatis survey, the UOE data have the advantage that they are available for significantly more host countries and countries of origin. On the other hand, the data documentation allows few conclusions to be drawn regarding the quality of the data (which varies significantly between host countries), and fewer differentiation factors (such as subject groups) are available.
Foreign students in Germany are recorded in the regular student statistics compiled by the Federal Statistical Office. These differentiate between Bildungsauslaender and Bildungsinlaender. The former are foreign students who gained their higher education entrance qualification from a school abroad (this also includes German schools abroad) or have attended a German preparatory college to complement a qualification gained at a school abroad. Bildungsinlaender are foreign students who gained their higher education entrance qualification at a school in Germany or have passed a gifted students test or an aptitude test in Germany. The Destatis data moreover make it possible to identify those Bildungsauslaender students who intend to graduate in Germany (see also previous section).
There are currently no official statistics covering temporary study-related international mobility (TSIM) of German students in its entirety. Official data are only available on the subsection of temporary study or placement visits conducted through the EU's Erasmus programme. These Erasmus visits represent around two thirds of temporary study-related visits abroad by German students. Thanks to the introduction of the new Higher Education Statistics Act, official data on study-related visits outside the Erasmus programme will be available in the near future (presumably by the 2018/19 winter semester). Until then, the number of temporary study-related visits abroad by German students will have to be estimated through student and graduate surveys.
For Bildungsauslaender in Germany on the other hand the figures on TSIM can be gleaned from the Destatis student statistics, which make it possible to identify Bildungsauslaender not intending to graduate in Germany or intending to graduate abroad (known as visiting students). The Erasmus statistics are available as an additional data source, although it must be borne in mind that the (enrolled) students they cover are also included in the Destatis student statistics. It is moreover important to note that data collected on temporary study-related visits abroad by Bildungsauslaender in Germany only cover study visits to higher education institutions; other study-related visits (e.g. placements, language courses, excursions) are not included in the Destatis and Erasmus statistics analysed here.
The findings presented here on degree-related international mobility of German students are based mainly on the statistic "German students abroad" from the Federal Statistical Office. For individual host countries, figures from the UNESCO statistics are used to complement these data. Along with the Erasmus statistics, the results of the DAAD/DZHW mobility surveys are the main source of data on temporary study-related visits abroad. These are the currently only regular surveys that specifically examine the international mobility of German students. Their findings are complemented with data from other surveys, such as the social survey performed by the German National Association for Student Affairs (in particular when examining longer-term trends) and the graduate studies conducted by DZHW and INCHER.
The main source of data on foreign students in Germany are the student statistics of the Federal Statistical Office, which differentiate between Bildungsauslaender, Bildungsinlaender and - for Bildungsauslaender - between students intending to graduate in Germany and those with no such intent. In addition, data on Erasmus participants from abroad who are conducting temporary study visits at German higher education institutions are analysed.
The UNESCO student statistics are used to analyse international student mobility.
B. Academic and researcher mobility
Forms of mobility
Based on their underlying reason for mobility, three basic types of closely related and often overlapping academic and researcher mobility can be distinguished: project- and event-related international mobility (e.g. conference trips, research projects abroad), qualification-related mobility (e.g. completion of a doctorate or post-doc project abroad) and workplace-related mobility (temporary or permanent research appointments abroad). In many cases, academic mobility can - depending on the perspective considered - be allocated to more than one of these types. Doctorate- or post-doc-related projects abroad are, for instance, often both project- and qualification-related. Apart from overlapping, these three types of academic mobility are also linked through various relationships of cause and effect. This also applies to the actual forms of mobility within the three mobility types. Completion of a first degree abroad, for example, often leads to doctorate-related mobility, which in turn may lead to post-doc mobility. Project-related academic mobility frequently results in event-related mobility, while contacts made at international scientific conferences regularly generate project-related academic mobility.
Available data sources and data quality
Research on international researcher mobility has to date been based mainly on three survey methods: evaluations of official or other publicly available statistics, analyses of publication databases (bibliometric data), and surveys. All three methods have strengths and weaknesses that are in some cases inverse to each other, i.e. the strength of one method is the weakness of the other and vice versa.
Evaluating publicly available statistics does not involve independent data collection, but rather uses existing datasets. This renders data collection effort unnecessary, which can be seen as a major advantage. Official data moreover frequently involve very large sample sizes or even full population surveys, which is a further strength of this method. Analysing publicly available data also has the advantage that findings can often easily be compared to those of other analyses that are based on the same data. The main constraint of this method is that it is limited to the variables available in the respective databases, which are often rather descriptive, and no additional variables can be collected that would allow a more in-depth analysis (e.g. of causes and effects of researcher mobility). In addition, only those researchers are included who are covered by official statistics, i.e. currently primarily researchers at public institutions. A further disadvantage of this method at present is the lack of international comparability of the data, as different definitions of "academics" and "researchers" are often applied and the quality and completeness of official data collection varies widely between countries.
Bibliometric analyses of academic and researcher mobility are based on international publication and citation databases; usually, one of the world's two major such databases, "Scopus" (Elsevier) or "Web of Science" (Thomson Reuters), is used. These databases catalogue a large proportion of all articles published in (English-language) academic journals, along with citations of these articles in other publications. The country of location of the author's institution is also documented for each item. As a result, these databases can be used to analyse international academic and researcher mobility, as comparing the countries of location for an author's various contributions permits conclusions regarding his or her mobility biography. The strengths of this method of analysis correspond largely to the strengths of evaluating publicly accessible statistics, i.e. no data collection effort is required, large sample sizes or full population surveys are available, and the results can be compared with other analyses that use the same publication database.
Despite the comprehensive datasets available for bibliometric analyses, such analyses are subject to some significant limitations: Firstly, access to the existing international publication databases is costly. Secondly, only researchers who are (already) publishing in the academic journals covered by the utilised publication databases are included. This applies mainly to English-language journals in natural and economic science disciplines; researchers in disciplines where monographs and edited volumes dominate (i.e. mainly the humanities and social sciences) are therefore almost entirely excluded. As there are also significant differences between countries regarding these publication cultures, and non-English language publications are moreover systematically underrepresented in most international publication databases, the informative value of international comparisons based on bibliometric analyses is limited. Bibliometric studies moreover do not allow comprehensive surveys of mobility biographies as mobility is only recorded when researchers actually publish papers (recorded in publication databases) in their respective countries of location both before and after mobility. In addition, academics and researchers can only be included in the sample from the time of their first recorded publication onwards. Any (potential) mobility before this first publication is therefore excluded, which may result in their mobility status and country of origin being determined incorrectly. For example, all researchers who have published in different countries during the reporting period will generally be considered mobile, with the first country of location during the reporting period considered their country of origin. It is therefore possible that earlier mobility is not factored in and a researcher's apparent country of origin is already a host country. Finally, at least two publications within the survey period are required to determine mobility. Consequently, young researchers who have no or only one journal publication to their name during the survey period are excluded from consideration.
In contrast to the two above-described methods, surveys are characterised in particular by the acquisition of new or primary data on researcher mobility. This has the advantage that survey managers can decide for themselves who exactly is surveyed and what questions are asked, i.e. which specific variables are collected. The amount of variables available for analysing researcher mobility is thus generally far higher with this method than when evaluating official statistics and publication databases, and this in turn allows for more in-depth and explanatory analyses (e.g. on motivations for and obstacles to mobility among researchers). It is moreover possible to include researchers in these analyses who are covered neither by publication databases nor by official statistics (e.g. researchers in private companies). Finally, international surveys of researchers can ensure that data from different countries is highly internationally comparable. However, surveys require significant effort and therefore cause significant costs. Due to these limitations, regular surveys are relatively infrequent and therefore unsuited as a basis for ongoing statistics on academic and researcher mobility.
"Wissenschaft weltoffen" uses a range of data sources to provide as comprehensive a picture as possible of academic and researcher mobility in Germany and other countries. The official statistics of the Federal Statistical Office (Destatis) on foreign academic personnel at state-approved higher education institutions and non-university research institutions and on enrolled international doctoral candidates are used to record foreign academics and researchers in Germany. In addition, data from the Erasmus statistics on short-term visits (Erasmus guest lecturers) and information requested by the DAAD and DZHW from relevant funding organisations on funded foreign guest researchers are analysed. With regard to the Destatis personnel statistics it should be noted that the recorded foreign academics and researchers are not necessarily always actually mobile academics and researchers, as the statistics only record information on citizenship, not on the country where the highest level of education was reached. It is therefore not possible to differentiate, as among foreign students, between Bildungsauslaender and Bildungsinlaender.
The available data on German academics and researchers abroad are currently still very incomplete, particularly with regard to longer-term visits (qualification- or employment-related international mobility). Short-term visits are covered by the Erasmus statistics on Erasmus guest lecturers and the previously mentioned requests for data from relevant funding organisations. These data are complemented by further requests by the DAAD and DZHW for data on German higher education personnel from the respectively responsible statistical offices in major host countries of German academics and researchers. The employment-related international mobility analysed here is thus subject to the respective country-specific definitions and limitations.
Finally, bibliometric data from the OECD and the American National Science Foundation, OECD data on international doctoral candidates worldwide and funding data from the contract database on the EU Framework Programme are used to analyse international academic and researcher mobility.