The construction of virtual science landscapes based on citation networks and the strategic use of the information therein
shed new light on the issues of the evolution of the science system and possibilities for control. Citations seem to have
a key position in the retrieval and valuation of information from scientific communication networks.Leydesdorff's approach to citation theory takes into account the dual-layered character of communication networks and the second-order
nature of the science system. This perspective may help to sharpen the awareness of scientists and science policy makers for
possible feedback loops within actions and activities in the science system, and probably nonlinear phenomena resulting therefrom.
In this paper an additional link to geometrically oriented evolutionary theories is sketched and a specific landscape concept
is used as a framework for some comments.
Competition is one of the most essential features of science. A new journal indicator - the"number of Matthew citations in a journal" was found that reflects certain aspects of thiscompetition. The indicator mirrors the competition of countries in scientific journals forrecognition in terms of seemingly "redistributed" citations.The indicator shows, as do other journal indicators, an extreme skewed distribution over anensemble of 2712 SCI journals. Half of all Matthew citations are contained in 144 so-calledMatthew core journals.In this paper, a new typology of scientific journals, including the Matthew core journals, isintroduced. For a few selected journals, graphs are presented showing national impact factors aswell as the absolute number of Matthew citations gained or lost by the countries publishing in thejournal.Scientific competition among countries for recognition is strongest in the Matthew corejournals, they are the most competitive markets for scientific publications. Conclusions are drawnfor national science policy, for the journal acquisition policy of national libraries, and for thepublication behaviour of individual scientists.
In this paper newly established characteristics of the so-called Matthew Effect for Countries (MEC) are presented: field-dependency,
time-stability, order of magnitude. We find that the MEC is observable in all main scientific fields that were investigated.
Over fifteen years the MEC has been relatively stable. The MEC is a redistribution phenomenon at the macro-level of the sciences.
Its magnitude is small; the MEC affects only about five percent of the world production of citations. The MEC, however, crucially
impacts many nations when their “national loss of citations” amounts to a high percentage of their expected citations. The
relationship between the MEC and Merton's Matthew Principle is discussed. It is our hypothesis that the MEC provides an additional
approach for the assessment of the scientific performance of nations.
In this paper we extend our studies to the micro-structure of the Matthew effect for countries (MEC). The MEC allows the ranking
of countries by their Matthew Index. The rank distribution of countries, observable only at a macro-level, has its roots in
re-distribution processes of citations in every journal of the database. These re-distributed citations we call Matthew citations.
Data for 44 countries and 2712 journals (based on theScience Citation Index) are analyzed. The strength of the contribution of the individual journals to the MEC (their number of Matthew citations)
is skewly distributed. Due to this high concentration of the MEC we are able to define a new type of journal the Matthew core
journal: 145 Matthew core journals account for 50% of the MEC. These journals carry a high potential of gaining a surplus
of citations over what is expected and the risk of losing a high number of citations as well.
A new indicator, Science Strategy Index, is proposed, which is based on the scattering of a country's science activity over all science fields and related to the world distribution of the science fields. The indicator allows to compare the structure of the publication output of countries as reflected by the used database, irrespective of the size of the countries.If the science structure of each country is related for comparison to that one of each other country, the indicator converts into a structure measure which enables to cluster countries according to their structural similarity. The cluster map of countries achieved in this way deserves intense discussion upon the different science strategies of countries and their geographic, political, communicative, and socio-cultural background.
This paper introduces a new approach to detecting scientists’ field mobility by focusing on an author’s self-citation network,
and the co-authorships and keywords in self-citing articles. Contrary to much previous literature on self-citations, we will
show that author’s self-citation patterns reveal important information on the development and emergence of new research topics
over time. More specifically, we will discuss self-citations as a means to detect scientists’ field mobility. We introduce
a network based definition of field mobility, using the Optimal Percolation Method (Lambiotte & Ausloos, 2005; 2006). The results of the study can be extended to selfcitation networks of groups of authors and, generally also
for other types of networks.
This paper shows maps of the web presence of the European Higher Education Area (EHEA) on the level of universities using
hyperlinks and analyses the topology of the European academic network. Its purpose is to combine methods from Social Network
Analysis (SNA) and cybermetric techniques in order to ask for tendencies of integration of the European universities visible
in their web presence and the role of different universities in the process of the emergence of an European Research Area.
We find as a main result that the European network is set up by the aggregation of well-defined national networks, whereby
the German and British networks are dominant. The national networks are connected to each other through outstanding national
universities in each country.