Bbliometrics and Urban Knowledge Urban Knowledge

Cities 29 (2012) S3–S8

Contents lists available at SciVerse ScienceDirect

Cities
journal homepage: www.elsevier.com/locate/cities

Bibliometrics and urban knowledge transfer
Judith Kamalski a,⇑, Andrew Kirby b
a
b

Elsevier, Radarweg 29, 1043 NX Amsterdam, Netherlands
Arizona State University, Phoenix, AZ 85069-7100, USA

a r t i c l e

i n f o

Article history:
Available online 5 July 2012

Keywords:
Bibliometrics
Urban research
Social sciences
Applied sciences

a b s t r a c t
This paper demonstrates the potential of bibliometric analysis in the context of urban studies. After a
brief discussion of the measurement of knowledge production, we provide an analysis of how the field
of urban studies is constructed. We do this in three contexts: first, in the narrowly defined population
of journals that constitutes the Thomson Reuters classification of urban studies; second, in the larger population of journals deemed to be within the social and behavioral sciences; and third, in a subset of the
applied sciences. We find that, by using keyword analysis, it is possible to identify three distinct spheres
of ‘urban knowledge’ that contain some overlap but also significant differences. We explore the significance of that for the development of urban studies.
Ó 2012 Elsevier Ltd. All rights reserved.

Introduction
To this point, research on the production of knowledge has been
dominated by a number of interrelated concerns. The first of these
would be what we can think of as the historical and philosophical
focus upon the creation of disciplines, and the processes of what

have been termed ‘normal science’. A second would be the determination of disciplinary content via the identification of keywords
and the construction of thesauri (Broughton, 2006). A third context
would be the manner in which methods and procedures have
evolved.
These concerns are all marked by their deductive emphasis,
placing well-known narratives into commonly-accepted structures
(Smolin, 2006). From at least one perspective, this is a teleological
approach that tells us how our science has progressed, told from
within the same structures of that very science. Little is known
of our scientific failures, false starts, and falsification experiments,
as they have been placed to one side: it is, if you will, a story told
only by winners—those who contribute to the dominant structures
of organized science and not by losers—those whose work is seen
to be marginalized.
There is, in contrast, a different approach to the production of
knowledge that eschews the deductive and the normative in favor
of the inductive and the empirical—simply, ‘what is’. In such a context, we can focus upon the production of information as it occurs,
without having to place any grids of understanding across the patterns of transfer.

⇑ Corresponding author. Tel.: +31 204852288.

E-mail addresses: j.kamalski@elsevier.com (J. Kamalski), andrew.kirby@asu.edu
(A. Kirby).
0264-2751/$ - see front matter Ó 2012 Elsevier Ltd. All rights reserved.
http://dx.doi.org/10.1016/j.cities.2012.06.012

This approach depends upon, and is facilitated by, the digital
transfer of information (e.g. Bollen et al., 2009). In the past, we
have been dependent upon relatively rigid methods of investigation into the relations between those who conduct science: in
terms of correspondence, say, or published collaborations. In the
present, we have more precise methods of measurement. Using
citation analyses, for example, we can construct elaborate diagrams that show exactly how individuals collaborate, or who cites
whom. We can aggregate these, and see how individuals, laboratories or ‘science cities’ are connected (or unconnected) in the global
flows of information (Bornmann & Leydesdorff, 2011).
We can now also go beyond these structures and examine the
links between the component parts of the academy as they exist
in practice. For instance, Bollen et al. have analyzed clickstream
data to show precisely how researchers research—or alternatively,
perhaps, how searchers search (2009). By following the trails of inquiry—clickstreams—we can see via aggregation which fields and
sub-fields are connected. This has almost nothing to do with a priori constructs such as disciplines, philosophies of science or method; instead it is scientific interaction in practice.

Connections within urban studies and why it matters
Urban studies is one of the longest established interdisciplinary fields within the modern academy. Indeed, massive urban
growth was a backdrop to the foundation of many universities at
the start of the 20th century, and a fundamental component of
disciplines, such as sociology, that confronted the emergence of
modernism as it manifested itself in these new metropolitan
settings. Yet this meant that the study of cities was woven into
many different disciplines, that had in consequence their own

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J. Kamalski, A. Kirby / Cities 29 (2012) S3–S8

Table 1
Data on urban publications in the three different clusters. Source: Scopus, February
2012.
Journals

Number of reviews and articles

Keywords

Urban studies cluster
Social sciences
Sciences

590
3719
2429

5109
32121
57629

urban specializations—urban anthropology, urban economics and
so forth. This has also been true in recent decades of the applied
sciences, where meteorology, climate and ecology have all become
tightly engaged with the processes of urban development. Nor is
this brief overview meant to ignore the humanities, where urban
history intersects with the concerns and technologies of the other

disciplines.
Yet this richness of material constitutes its own problems. For
the most part, urban studies has never been destined to emerge
as a freestanding discipline, and in fact its nearest neighbors—such
as urban and regional (or town and country) planning—have been
in a phase of transformation for many years (Campanella, 2011). It
has its own journals of course, and its own subject classification in
the Thomson Reuters schema, but these account for only a small
proportion of the material published in the broader context of urban analysis (e.g. Liu, 2005). A recent paper documents some of
these ways in which the field has evolved over the past two decades (Wang, He, Liu, Zhuang, & Hong, 2012).
This situation has led to two outcomes: first, there is some
redundancy in the research that is published in different sub-fields
but overall, there is little convergence between the different
strands of urban research. This is especially true when different
methodologies and/or different ideological outlooks are factored
in. Second, and in consequence, it is a challenge for researchers
to maintain any systematic awareness of work being done in distant fields, albeit with similar urban content: this is especially true
of research in transport, ecology, risk management and climate
change.

We limited the search to social science subject areas and to relevant subject areas in the applied sciences. We ignored medicine,
engineering and similar fields as this research was, once again,
undertaken in urban contexts but did not contribute to urban
scholarship; a typical example would be technical studies of atmospheric chemistry that use urban and rural samples but have no
policy content. This yielded the following numbers of articles and
reviews (see Table 1).
As a second step of our analysis, we looked at frequencies of
keywords attributed by indexers such as MEDLINE and Embase.
Redundancies were eliminated and minor categories collapsed:
e.g. ‘water use’ and ‘water planning’ were aggregated to ‘water’.
The three data sets were rearranged according to the keyword frequency, and scaled against the grand totals for each column, in order to make the columns comparable (e.g. 502 as a proportion of
32121 = 156, the first entry in the social sciences column).
Results
In Table 2 we show the top twenty rankings of the aggregated
key words for the three groups of journals. In red we indicate keywords that are unique to a single column; in blue we show those
that are shared across all three columns.
The table indicates that there is a high degree of divergence between the three groups of journals, with 21 of the keyword entries
being unique and only 20 appearing on all three lists; in a situation
of complete convergence there would be a total of only 20 entries,
in a situation of total divergence there would be 60 unique entries.

The social science journals show the least individuality, with
only three unique keywords. The applied science journals display
an emphasis on research on urban areas that is linked to environmental issues; keywords include air, atmosphere, water and the
environment itself. In addition, this column contains the very specific policy component—sustainability. The urban column stands in
marked contrast, beginning with housing and continuing through
topics such as urban renewal.
We also examined all the keywords in terms of their frequency
of appearance, and the frequency of citation. These are displayed in
Figs. 1–3.

Research strategy
Assessment
In order to explore these issues systematically, we examined
the convergences and divergences in the different branches of urban research. First, we identified three distinct clusters of published material:
1. the research published within the 38 journals that constitute
the urban studies cluster within the Thomson Reuters classification of research journals;
2. the research published within the journals that together publish urban material from the social sciences and the humanities;
3. the research with urban content published in the applied
sciences.1
In the SciVerse-Scopus database of journal articles published in

2010, which contains 991,000 entries, we identified research papers containing the keyword ‘urban’ plus one of the following keywords—planning, renewal, development, politics, population,
transport, housing—that have shown up in a pilot project. (Papers
without these keywords tend to be focused on research undertaken
in cities rather than rural areas, but are not adding to urban scholarship as such.)
1
For simplicity, we simply ignored journals publishing chemistry, medicine and so
forth. A full list of search queries may be obtained from the authors.

We believe that even this simple assessment reveals a great
deal about the field of urban studies. The most significant item is
the divergence in content, especially with regard to the applied sciences on the one hand, and the explicitly urban studies journals on
the other.
As noted, the applied sciences have an emphasis upon what we
might broadly think of as environmental research. This is not in
any sense surprising, but what is astonishing is the absence of
these terms from the higher rankings of the other two columns.
Our study demonstrates a virtual silence on these topics in the social science literature, even after a decade of public discussion
about climate change. The same is true of—and this is perhaps even
more surprising—sustainability. We should expect the latter to be a
field where applied science and social science reinforce each other,

but that seems not to be occurring.
There is also a significant divergence with respect to methods.
Geographic Information Systems (GISs) appear only in the applied
sciences. We can also see differences with regard to scale. Social
science research on cities pays attention to the neighborhood,
which is where research on housing, public goods and crime is
done. In contrast, applied science research can be thought of as
scale-free, meaning that it is usually done at the metropolitan level
or any sub-national scale for which data are available.

J. Kamalski, A. Kirby / Cities 29 (2012) S3–S8

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Table 2
Most frequent appearances of keywords in the three clusters: those in red are unique, those in blue are common to all three columns, and those shaded are discussed below. Based
on data taken from Scopus, February 2012.

Fig. 1. Word cloud for urban studies; articles from 2008 and 2009;citations in 2010.

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J. Kamalski, A. Kirby / Cities 29 (2012) S3–S8

Fig. 2. Word cloud for social sciences, articles from 2008 and 2009, citations in 2010.

Fig. 3. Word cloud for applied sciences, articles from 2008 and 2009, citations in 2010.

J. Kamalski, A. Kirby / Cities 29 (2012) S3–S8

Explanations and origins
Accounting for these differences fully would require a booklength statement. We can though touch on a couple of topics here.
One is the way in which urban journals have evolved; the second
relates to national origins.
The content of urban journals has clear clusters: Liu has suggested one way to make sense of these (2005). Another interpretation would be to emphasize that the field is still highly fragmented.
To take the case of the US, we can see that the journals that are
most visible (such as the Journal of Urban Affairs and Urban Affairs
Review) have been closely connected with political science and
public administration. One way that this then manifests itself is
in terms of a lack of historical research (Harris & Smith, 2011).
We can see therefore that the field is still emergent—to use the
heuristic terminology developed by Ramadier, we could suggest
that urban studies is still moving from a disciplinary to a multidisciplinary focus; ahead of it lies a truly interdisciplinary era, and
then in turn it could emerge as a transdisciplinary field in its
own right (Ramadier, 2004): see Fig. 4. Ramadier uses the following example, but then demonstrates the inherent challenges by

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choosing only the social and behavioral sciences and erasing the
humanities, the physical and the environmental sciences: ‘‘an urban planner attributes the legibility of a city to its physical characteristics, a sociologist will attribute it to the different meanings
tied to the experience of individuals in the city, and a psychologist
will pay attention to the behavior of individuals in space’’ (Ramadier, 2004, p. 434).
In short then, fragmentation in urban studies may be a function
of its evolutionary development—a point we will return to again in
the Conclusion. A second factor is also important, and that
connects to national origins. Bibliometric studies indicate that
the global marketplace of ideas, albeit published in English, is still
dominated by Western authors, who are much more likely to cite
each other. Asian, Latin American and African authors remain
under-cited (see for example Bornmann & Leydesdorff, 2011).
In the study reported here, there is a clear distinction
between the publications in the applied sciences and those in the
other two columns, with a much higher proportion of the former
coming from China, and a higher proportion of the latter emanating from Western scholars. We can display these differences in
Fig. 5.

Fig. 4. the progression of disciplinary to transdisciplinary research: adapted from Ramadier.

Fig. 5. The most prolific countries for ‘urban’ research, contrasting urban studies, social sciences and applied sciences. Source: Scopus

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J. Kamalski, A. Kirby / Cities 29 (2012) S3–S8

In Fig. 5, we show for the most prolific countries the percentage
of papers within a category that have at least one author with an
affiliation in this country. For instance, the blue2 column for the
US shows that 33% of all urban studies papers have an author with
an American affiliation. It shows a completely different pattern for
China than for prolific countries such as the United States and United
Kingdom. China publishes a remarkable percentage of all applied sciences papers in this subject area, and a relatively small amount of
urban studies or social science papers in the same area. European
countries such as Spain, Germany, France, and Italy show a similar
pattern, albeit less obviously. We also see this in Brazil, Japan, and
India.
For urban studies, there are a few prolific countries and many
countries with lower numbers of output. For urban research in
the social sciences or the sciences, the difference between the
countries is smaller.
There are important processes at work here that count for these
differences. In the West, a model of science has emphasized the
domination of nature and this has only relatively recently been
challenged. In consequence, urban research in general, and work
on planning in particular, has neglected the environmental context: the small number of papers discussing adaption to climate
change would be an example of this. In contrast, Chinese authors
have been, until quite recently, constrained in the topics that they
can study and on which they can publish. It is therefore unsurprising that they have not focused on urban inequalities, but have
turned to resource conditions.
Discussion and further research
This example began life as a thought experiment that asked if
there are distinct arenas of urban thought, not merely within the
urban cluster of journals, but beyond? This paper demonstrates,
we believe, that such clusters do indeed exist.
On one level, a level of specialization is unremarkable—indeed,
the academy is moving towards greater specificity in terms of journals and the researchers who publish there. But this is also troublesome insofar as it promotes duplication on the one hand, and
talking past one another on the other. Stephanie Pincetl offers an
excellent example of how this occurs in her discussion of urban
ecology, elsewhere in this issue (Pincetl, in press).
The purpose of placing this example in print is also to illuminate
one of the key goals of this journal, namely to promote conversations between these urban clusters. Some scientific research might
benefit from thinking about the city at scales such as the neighbor-

2
For interpretation of color in Figs. 1–3 and 5, the reader is referred to the web
version of this article.

hood; conversely, more explicitly urban work must engage with
environmental issues and, explicitly, the development of the literature on sustainability, resilience and adaptation.

Conclusions
Bibliometric research can provide useful insights into the structure and characteristics of a specific subject field. However, there
will always be a need to contrast these findings with expert opinions, to ensure meaningful interpretation. We believe that our collaboration, coming from very different traditions, provides a useful
example of this principle.
It is our intention to extend the research that we have started
here, looking at specific components of the sprawling urban literature. We do this, in part, as an example of what bibliometrics can
accomplish; but we are also mindful that urban studies is an
important—and evolving—field. It is a cliché that ours is an urbanizing planet, and that many policy challenges reside in urban areas.
Consequently, anything that can be done to make this a truly interdisciplinary field is a valuable addition to its practice. We hope to
have these follow-up studies in the journal in upcoming issues.

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