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- July 8, 2020. The CWTS Leiden Ranking 2020 has been published. More information is available in this blog post.
- June 30, 2020. Together with Aaron Tay and Bianca Kramer, I have published the blog post Why openly available abstracts are important - overview of the current state of affairs.
- May 22, 2020. The paper Large-scale comparison of bibliographic data sources: Scopus, Web of Science, Dimensions, Crossref, and Microsoft Academic by Martijn Visser, Nees Jan van Eck, and Ludo Waltman has been published in arXiv.
- May 14, 2020. The paper Use of the journal impact factor for assessing individual articles need not be statistically wrong by Ludo Waltman and Vincent A. Traag has been published in F1000Research. The paper has not yet been peer reviewed.
- April 20, 2020. The paper A scientometric overview of CORD-19 by Giovanni Colavizza, Rodrigo Costas, Vincent A. Traag, Nees Jan van Eck, Thed van Leeuwen, and Ludo Waltman has been published in bioRxiv.
- April 20, 2020. The paper Algorithmic labeling in hierarchical classifications of publications: Evaluation of bibliographic fields and term weighting approaches by Peter Sjögårde, Per Ahlgren, and Ludo Waltman has been published in arXiv.
- April 1, 2020. VOSviewer version 1.6.15 has been released and is available for download. This new version of VOSviewer offers improved support for querying the Microsoft Academic API.
- February 20, 2020. The first issue of Quantitative Science Studies has been published.
- January 27, 2020. VOSviewer version 1.6.14 has been released and is available for download. This new version of VOSviewer offers improved support for querying APIs.
- January 15, 2020. The paper Intermediacy of publications by Lovro Subelj, Ludo Waltman, Vincent Traag, and Nees Jan van Eck has been published in Royal Society Open Science.
- September 30, 2019. The Research on Research Institute (RoRI), a collaboration of Wellcome Trust, Digital Science, University of Sheffield, and Leiden University, has been launched. The institute has made available an online tool for exploring research funding landscapes.
- September 16, 2019. VOSviewer version 1.6.13 has been released and is available for download. This new version provides a few minor bug fixes.
- August 31, 2019. VOSviewer version 1.6.12 has been released and is available for download. This new version of VOSviewer offers support for working with Microsoft Academic data.
- August 1, 2019. Read my opinion piece Put metrics in context in Research Europe.
- May 28, 2019. The comment Rethinking impact factors: Better ways to judge a journal, co-authored with Paul Wouters, Cassidy R. Sugimoto, Vincent Larivière, Marie E. McVeigh, Bernd Pulverer, and Sarah de Rijcke and supported by 18 co-signatories, has been published in Nature.
I am professor of Quantitative Science Studies at CWTS. The work of my research group is organized in the following research lines:
- Bibliometric data sources
- Contextualized scientometrics
- Modeling the research system
- Scientometric tools
I am also Deputy Director of CWTS, coordinator of the CWTS Leiden Ranking, co-developer of the VOSviewer software for scientometric visualization, and Editor-in-Chief of Quantitative Science Studies.
A list of my publications is available here.