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A Large-Scale Analysis of Impact Factor Biased Journal Self-Citations

Based on three decades of citation data from across scientific fields of science, we study trends in impact factor biased self-citations of scholarly journals, using a purpose-built and easy to use citation based measure. Our measure is given by the ratio between i) the relative share of journal self-citations to papers published in the last two years, and ii) the relative share...

Citation-based clustering of publications using CitNetExplorer and VOSviewer

Clustering scientific publications in an important problem in bibliometric research. We demonstrate how two software tools, CitNetExplorer and VOSviewer, can be used to cluster publications and to analyze the resulting clustering solutions. CitNetExplorer is used to cluster a large set of publications in the field of astronomy and astrophysics. The publications are clustered...

Clustering Scientific Publications Based on Citation Relations: A Systematic Comparison of Different Methods

Clustering methods are applied regularly in the bibliometric literature to identify research areas or scientific fields. These methods are for instance used to group publications into clusters based on their relations in a citation network. In the network science literature, many clustering methods, often referred to as graph partitioning or community detection techniques, have...

Exploring the Relationship between the Engineering and Physical Sciences and the Health and Life Sciences by Advanced Bibliometric Methods

We investigate the extent to which advances in the health and life sciences (HLS) are dependent on research in the engineering and physical sciences (EPS), particularly physics, chemistry, mathematics, and engineering. The analysis combines two different bibliometric approaches. The first approach to analyze the ‘EPS-HLS interface’ is based on term map visualizations of HLS...

A mathematical analysis of the long-run behavior of genetic algorithms for social modeling

Ludo Waltman 0 Nees Jan van Eck 0 0 L. Waltman (&) N. J. van Eck Econometric Institute, Erasmus School of Economics, Erasmus University Rotterdam , P.O. Box 1738, 3000 DR Rotterdam, The Netherlands

Economic modeling using evolutionary algorithms: the effect of a binary encoding of strategies

Ludo Waltman Nees Jan van Eck Rommert Dekker Uzay Kaymak We are concerned with evolutionary algorithms that are employed for economic modeling purposes. We focus in particular on evolutionary

A recursive field-normalized bibliometric performance indicator: an application to the field of library and information science

Two commonly used ideas in the development of citation-based research performance indicators are the idea of normalizing citation counts based on a field classification scheme and the idea of recursive citation weighing (like in PageRank-inspired indicators). We combine these two ideas in a single indicator, referred to as the recursive mean normalized citation score indicator...

Software survey: VOSviewer, a computer program for bibliometric mapping

We present VOSviewer, a freely available computer program that we have developed for constructing and viewing bibliometric maps. Unlike most computer programs that are used for bibliometric mapping, VOSviewer pays special attention to the graphical representation of bibliometric maps. The functionality of VOSviewer is especially useful for displaying large bibliometric maps in an...

Citation Analysis May Severely Underestimate the Impact of Clinical Research as Compared to Basic Research

basic and diagnostic research. - Competing Interests: Nees Jan van Eck, Ludo Waltman, and Anthony F. J. van Raan are affiliated with the Centre for Science and Technology Studies of Leiden University

On the correlation between bibliometric indicators and peer review: reply to Opthof and Leydesdorff

Opthof and Leydesdorff (Scientometrics, 2011) reanalyze data reported by Van Raan (Scientometrics 67(3):491–502, 2006) and conclude that there is no significant correlation between on the one hand average citation scores measured using the CPP/FCSm indicator and on the other hand the quality judgment of peers. We point out that Opthof and Leydesdorff draw their conclusions based...

Towards a new crown indicator: an empirical analysis

We present an empirical comparison between two normalization mechanisms for citation-based indicators of research performance. These mechanisms aim to normalize citation counts for the field and the year in which a publication was published. One mechanism is applied in the current so-called crown indicator of our institute. The other mechanism is applied in the new crown...

Automatic term identification for bibliometric mapping

A term map is a map that visualizes the structure of a scientific field by showing the relations between important terms in the field. The terms shown in a term map are usually selected manually with the help of domain experts. Manual term selection has the disadvantages of being subjective and labor-intensive. To overcome these disadvantages, we propose a methodology for...