, Volume 87, Issue 1, pp 149–158 | Cite as

International collaboration in psychology is on the rise

  • Reinhold KlieglEmail author
  • Douglas Bates


There has been a substantial increase in the percentage for publications with co-authors located in departments from different countries in 12 major journals of psychology. The results are evidence for a remarkable internationalization of psychological research, starting in the mid 1970s and increasing in rate at the beginning of the 1990s. This growth occurs against a constant number of articles with authors from the same country; it is not due to a concomitant increase in the number of co-authors per article. Thus, international collaboration in psychology is obviously on the rise.


International collaboration Psychological publications Linear mixed model Historical trend 



We thank Bernhard Angele and Steffen Kleinschmidt for help with assembling the data base and Barbara Krahé. Keith Rayner, and Eike Richter for helpful comments.


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Copyright information

© Akadémiai Kiadó, Budapest, Hungary 2010

Authors and Affiliations

  1. 1.Department of PsychologyUniversity of PotsdamPotsdamGermany
  2. 2.Department of StatisticsUniversity of WisconsinMadisonUSA

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