International Co-authorship Relations in the Social Science Citation Index: Is Internationalization Leading the Network?

International co-authorship relations have increasingly shaped another dynamic in the natural and life sciences during recent decades. However, much less is known about such internationalization in the social sciences. In this study, we analyze international and domestic co-authorship relations of all citable items in the DVD-version of the Social Science Citation Index 2011 (SSCI). Network statistics indicate four groups of nations: (i) an Asian-Pacific one to which all Anglo-Saxon nations (including the UK and Ireland) are attributed; (ii) a continental European one including also the Latin-American countries; (iii) the Scandinavian nations; and (iv) a community of African nations. Within the EU-28, eleven of the EU-15 states have dominant positions. In many respects, the network parameters are not so different from the Science Citation Index. In addition to these descriptive statistics, we address the question of the relative weights of the international versus domestic networks. An information-theoretical test is proposed at the level of organizational addresses within each nation; the results are mixed, but the international dimension is more important than the national one in the aggregated sets (as in the Science Citation Index). In some countries (e.g., France), however, the national distribution is leading more than the international one. Decomposition of the USA in terms of states shows a similarly mixed result; more US states are domestically oriented in SSCI, whereas more internationally in SCI. The international networks have grown during the last decades in addition to the national ones, but not by replacing them.