EDITORIAL
Special issue on bibliographic data sources
Ludo Waltman1
and Vincent Larivière2,3
1Centre for Science and Technology Studies (CWTS), Universidad de Leiden, Leiden, Los países bajos
2École de bibliothéconomie et des sciences de l’information, Université de Montréal, Montréal, Quebec, Canada
3Observatoire des Sciences et des Technologies (OST), Centre Interuniversitaire de Recherche sur la Science et la Technologie
(CIRST), Université du Québec à Montréal, Montréal, Quebec, Canada
1.
INTRODUCCIÓN
Research in quantitative science studies relies on an increasingly broad range of data sources,
providing data on scholarly publications, social media activity, peer review, research funding,
the scholarly workforce, scientific prizes, etcétera. Sin embargo, there is one type of data source
that remains at the heart of research in quantitative science studies: bibliographic databases.
These data sources have increasingly diversified over the last decade. Several organizations
now provide large-scale databases of metadata on scholarly publications. For this special issue
of Quantitative Science Studies, we invited the providers of major bibliographic data sources
to provide insights on how their data can be used to support research in quantitative science
estudios.
This special issue comprises six papers. Three papers cover the most important commercial
bibliographic data sources: Web of Science (Clarivate Analytics), Scopus (Elsevier), y
Dimensions (Digital Science). Three other papers cover open data sources: Microsoft
Académico, Crossref and OpenCitations.1 There are of course many other bibliographic data
sources. Sin embargo, for this special issue, we have chosen to consider only data sources that
cover publications from all fields of science and from all parts of the world. Data sources that
focus on specific scientific fields (p.ej., PubMed from the US National Library of Medicine) o
specific countries (p.ej., national databases of scholarly publications) are therefore not
incluido.
We hope that this special issue will help authors of submissions to Quantitative Science
Studies to choose the most suitable bibliographic data source for their research. In the past,
Web of Science and Scopus often were the only data sources between which researchers
could choose. Researchers typically used the data source to which their institution happened
to have a subscription. En años recientes, sin embargo, the number of options has increased consid-
erably. This special issue aims to characterize the most important data sources currently avail-
able and to show how they differ in various dimensions, for instance in the data they provide,
their level of openness, and their support for making research reproducible. As editors of
Estudios de ciencias cuantitativas, we consider openness and reproducibility to be of major impor-
tance. Research published in Quantitative Science Studies is expected to be as reproducible as
posible, and reproducibility can be promoted by making use of open data.
Below we provide a brief overview of some of the key differences between the bibliographic
data sources considered in this special issue, focusing on three questions: What does the data
source provide? How to get access to the data? And how can the data be used?
1 The team of Google Scholar was also invited to contribute to this special issue, but they did not respond to
un acceso abierto
diario
Citación: waltman, l., & Larivière, V.
(2020). Special issue on bibliographic
data sources. Quantitative Science
Estudios, 1(1), 360–362. https://doi.org/
10.1162/qss_e_00026
DOI:
https://doi.org/10.1162/qss_e_00026
Autor correspondiente:
Juego Waltman
waltmanlr@cwts.leidenuniv.nl
Derechos de autor: © 2020 Ludo Waltman and
Vincent Larivière. Published under a
Creative Commons Attribution 4.0
Internacional (CC POR 4.0) licencia.
La prensa del MIT
our invitation.
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Q1
Special issue on bibliographic data sources
2. WHAT DOES THE DATA SOURCE PROVIDE?
Web of Science and Scopus are selective data sources. Both the Web of Science Core
Collection and Scopus aim to cover only content that meets certain standards. These data
sources for instance try to make sure they do not cover journals that adopt questionable pub-
lication practices (‘predatory journals’). In the case of Scopus, content selection is carried out
by an external Content Selection and Advisory Board consisting of independent researchers.
Rather than being selective, the other data sources aim to be comprehensive. Microsoft
Academic obtains most of its data by crawling the Web, although it also makes use of data pro-
vided by publishers. Microsoft decides which content retrieved from the Web is considered to
be of a scholarly nature and deserves to be included in Microsoft Academic. Data curation is
performed using artificial intelligence techniques. Human intervention is minimized as much as
posible. Crossref obtains its data from publishers that work with Crossref to obtain digital object
identifiers (DOIs) for their content. Publishers decide whether they want to work with Crossref
and what data they want to make available through Crossref. Dimensions builds on data from
sources such as Crossref and PubMed, and complements this data with data received from pub-
lishers. Finalmente, OpenCitations also obtains its data from other sources, such as Crossref and
PubMed Central. It does not receive data from publishers. In addition to other formats,
OpenCitations makes its data available in RDF format as linked open data, using semantic
web technologies.
3. HOW TO GET ACCESS TO THE DATA?
Access to Web of Science and Scopus normally requires a payment. Dimensions has a free
and a paid version. The paid version offers additional features not available in the free version.
It for instance provides access to data that is not accessible in the free version. For research
purposes, it is possible to apply for no-cost access to the full version of Dimensions, incluido
access through an API. Asimismo, Elsevier’s International Center for the Study of Research plans
to create a ‘virtual laboratory’ that provides free access to Scopus data for research purposes.
While Dimensions data has already been made available for bibliometric research, the details
of Elsevier’s plan are not yet clear at the moment.
Microsoft Academic, Crossref, and OpenCitations make all their data openly available.
Microsoft Academic can be queried through an API. Up to a certain limit, this API can be used
free of charge. Crossref and OpenCitations can also be queried through APIs. Their APIs can
be freely used without any limit. Crossref also offers a paid service called Metadata Plus, cual
provides improved API access and the possibility to download a snapshot of the full Crossref
database. A snapshot of the full Microsoft Academic database can be downloaded through
Microsoft’s Azure platform. A small fee may be required to cover the costs associated with
the use of this platform. OpenCitations also releases snapshots of its databases. These snap-
shots can be freely downloaded.
4. HOW CAN THE DATA BE USED?
All data sources allow their data to be used for research purposes. For some of the data
sources, in particular Web of Science and Dimensions, the providers ask researchers that
use their data to share their results and to report problems identified in the data.
Idealmente, bibliographic data used in research projects is made openly available. El COM-
mercial data sources ( Web of Science, Scopus, and Dimensions) do not allow their data to be
made openly available. They impose restrictions on the sharing or redistribution of their data.
Estudios de ciencias cuantitativas
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Special issue on bibliographic data sources
Such restrictions make it more difficult to reproduce research based on data from these
sources. Even if different research teams all have access to a specific data source, it may be
hard for one team to reproduce the work of another team, as the data is a moving target
because of continuous updates of the data source. To address this problem, data providers
would need to provide access to archived time-stamped versions of their data.
Microsoft Academic, Crossref, and OpenCitations make their data openly available.
Researchers are therefore allowed to share or redistribute their data, which makes research
easier to reproduce. Microsoft Academic releases its data under an ODC-BY license. This li-
cense requires Microsoft to be acknowledged when Microsoft Academic data is used. Crossref
considers its data to be facts. The data cannot be owned and is therefore made available with-
out a license. Finalmente, OpenCitations makes its data available under a CC0 license, releasing
the data into the public domain and minimizing restrictions on the use of the data.
5. CONCLUSIÓN
We hope that this special issue will help researchers working with bibliographic data to better
understand the characteristics of different data sources and to choose the most suitable data
source for their research. There are advantages and disadvantages to each data source. Mientras
the selectivity of Web of Science and Scopus may for instance be beneficial for some studies, él
may be problematic for others. Asimismo, some studies may use an open data source because
reproducibility is considered essential, while other studies may have to rely on a closed data
source because they require data that is not openly available.
This special issue does not provide comparisons of the different data sources in terms of
their coverage, completeness, and data quality. Such comparisons can best be performed
by independent research groups rather than by the data providers themselves. Submissions
of papers presenting comparisons of the data provided by different bibliographic data sources
are very much welcomed at Quantitative Science Studies. We hope to publish such papers in
the near future.
Finalmente, we would like to express our gratitude to Clarivate Analytics, Elsevier, Digital
Ciencia, Microsoft, Crossref, and OpenCitations for working together with us in making this
special issue possible.
CONFLICTO DE INTERESES
Ludo Waltman is deputy director of the Centre for Science and Technology Studies (CWTS) en
Universidad de Leiden. CWTS has commercial relationships with Clarivate Analytics, Elsevier, y
Digital Science. CWTS and Digital Science also work together as founding partners of the
Research on Research Institute (RoRI; http://researchonresearch.org). Waltman works together
with OpenCitations in his capacity as chair of the Advisory Board of the Research Centre for
Open Scholarly Metadata.
Vincent Larivière is associate scientific director of the Observatoire des sciences et des
technologies at Université du Québec à Montréal (OST-UQAM). OST-UQAM has a commer-
cial relationship with Clarivate Analytics. Larivière also sits on the Advisory Board of the
Research Centre for Open Scholarly Metadata.
Estudios de ciencias cuantitativas
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