The decline in the concentration of citations, 1900–2007

This article challenges recent research (Evans, 2008) reporting that the concentration of cited scientific literature increases with the online availability of articles and journals. Using Thomson Reuters’ Web of Science, the present article analyses changes in the concentration of citations received (2- and 5-year citation windows) by papers published between 1900 and 2005.Three measures of concentration are used: the percentage of papers that received at least one citation (cited papers); the percentage of papers needed to account for 20%,50%, and 80% of the citations; and the Herfindahl-Hirschman index (HHI). These measures are used for four broad disciplines: natural sciences and engineering, medical fields, social sciences, and the humanities. All these measures converge and show that, contrary to what was reported by Evans, the dispersion of citations is actually increasing

Does collaborative research published in top journals remain uncited?

This paper investigates whether collaborative research published in top journals remains uncited, and to what extent access type (open and closed) affects on citation of collaborative research published in top journals. It looks at publications including articles, conference papers, reviews, short surveys, editorials, letters, notes published between 2009-2016 with an affiliation from Chalmers University of Technology and indexed in Scopus. To giveenough time to gather citation, two-year time frame is considered for the publication of the year 2016. The data is classified based on access types: closed and open access, and sub-classified as cited closed access, cited open access, non-cited closed access, and non-cited open access in SciVal. The top 25 percentile indicating the number of journals that are in the top 25% of the most cited journals indexed by Scopus is considered. The result showsthat a small portion of collaborative research published in top journals remain uncited irrespective of types of collaboration. In case of international collaborative research, publications in closed access are more cited than in open access. Institutional collaborative research publications are more cited than national collaborative ones. Collaborative research is more cited than single authors’ publications and single authored conference paperspublished in the top percentile do not remain uncited

Modeling a century of citation distributions

The prevalence of uncited papers or of highly cited papers, with respect to the bulk of publications, provides important clues as to the dynamics of scientific research. Using 25 million papers and 600 million references from the Web of Science over the 1900–2006 period, this paper proposes a simple model based on a random selection process to explain the “uncitedness” phenomenon and its decline over the years. We show that the proportion of cited papers is a function of (1) the number of articles available (the competing papers), (2) the number of citing papers and (3) the number of references they contain. Using uncitedness as a departure point, we demonstrate the utility of the stretched-exponential function and a form of the Tsallis q-exponential function to fit complete citation distributions over the 20th century. As opposed to simple power-law fits, for instance, both these approaches are shown to be empirically well-grounded and robust enough to better understand citation dynamics at the aggregate level. On the basis of these models, we provide quantitative evidence and provisional explanations for an important shift in citation practices around 1960. We also propose a revision of the “citation classic” category as a set of articles which is clearly distinguishable from the rest of the field

What do chemists cite? A five-year analysis of references cited in American Chemical Society journal articles.

This study analyzes references cited by articles published in ten American Chemical Society journals between 2011 and 2015. The median age of references was 6 years. On average, 44% of the references were five years old or younger, and only 11% were more than 20 years old. There appears to be a modest increase in references to older sources, possibly due to the increased availability of older articles online. References tended to be concentrated on a small core of journals. Overall, 20% of the journals cited accounted for 80% of the references. However, there was considerable variation among subdisciplines

What do chemists cite? A five-year analysis of references cited in American Chemical Society journal articles.

This study analyzes references cited by articles published in ten American Chemical Society journals between 2011 and 2015. The median age of references was 6 years. On average, 44% of the references were five years old or younger, and only 11% were more than 20 years old. There appears to be a modest increase in references to older sources, possibly due to the increased availability of older articles online. References tended to be concentrated on a small core of journals. Overall, 20% of the journals cited accounted for 80% of the references. However, there was considerable variation among subdisciplines

What do chemists cite? A five-year analysis of references cited in American Chemical Society journal articles

This study analyzes references cited by articles published in ten American Chemical Society journals between 2011 and 2015. The median age of references was 6 years. On average, 44 percent of the references were five years old or younger, and only 11 percent were more than 20 years old. There appears to be a modest increase in references to older sources, possibly due to the increased availability of older articles online. References tended to be concentrated on a small core of journals. Overall, 20 percent of the journals cited accounted for 80 percent of the references. However, there was considerable variation among sub-disciplines

What do chemists cite? A five-year analysis of references cited in American Chemical Society journal articles

This study analyzes references cited by articles published in ten American Chemical Society journals between 2011 and 2015. The median age of references was 6 years. On average, 44 percent of the references were five years old or younger, and only 11 percent were more than 20 years old. There appears to be a modest increase in references to older sources, possibly due to the increased availability of older articles online. References tended to be concentrated on a small core of journals. Overall, 20 percent of the journals cited accounted for 80 percent of the references. However, there was considerable variation among sub-disciplines

Identification of research communities in cited and uncited publications using a co-authorship network

Patterns of co-authorship provide an effective means of probing the structures of research communities. In this paper, we use the CiteSpace social network tool and co-authorship data from the Web of Science to analyse two such types of community. The first type is based on the cited publications of a group of highly productive authors in a particular discipline, and the second on the uncited publications of those highly productive authors. These pairs of communities were generated for three different countries—the People’s Republic of China (PRC), the United Kingdom (UK) and the United States of America (USA)—and for four different disciplines (as denoted by Web of Science subject categories)—Chemistry Organic, Engineering Environmental, Economics, and Management. In the case of the UK and USA, the structures of the cited and uncited communities in each of the four disciplines were markedly different from each other; in the case of the PRC, conversely, the cited and uncited PRC communities had broadly similar structures that were characterised by large groups of connected authors. We suggest that this may arise from a greater degree of guest or honorary authorship in the PRC than in the UK or the USA