| Abstract: |
This paper studies the assignment of responsibility to the participants in the
case of co-authored scientific publications. In the conceptual part, we
establish that the key shortcoming of the full counting method is its
incompatibility with the use of additively decomposable citation impact
indicators. In the empirical part of the paper, we study the consequences of
adopting the address-line fractional or multiplicative counting method. For
this purpose, we use a Web of Science dataset consisting of 3.6 million
articles published in the 2005-2008 period, and classified into 5,119
clusters. Our research units are the 500 universities in the 2013 edition of
the CWTS Leiden Ranking. Citation impact is measured using the Mean Normalized
Citation Score, and the Top 10% indicators. The main findings are the
following. Firstly, although a change of counting methods alters co-authorship
and citation impact patterns, cardinal differences between co-authorship rates
and between citation impact values are generally small. Nevertheless, such
small differences generate considerable re-rankings between universities.
Secondly, the universities that are more penalized by the adoption of a
fractional rather than a multiplicative approach are those with a small
co-authorship rate for the citation distribution as a whole, a large
co-authorship rate in the upper tail of this distribution, a low citation
impact performance, and a small number of solo publications. |