Improving the functionality of interactive bibliometric science maps

The use of a map as a metaphor of a scientific field is an established idea and using it as aninterface to bibliometric data seems to have great potential. Nevertheless, our own implementationof such an interface came up with some limits inhibiting the user to comprehend as to what hewas looking at. As a result, the map was not used to its fullest potential. The implementationdescribed in this paper as a high-level (conceptual) design, addresses the problems noted by users.It combines both top-down and bottom-up access to the bibliometric data, something we see asvital to mapping internal knowledge onto the external depiction and vice versa. And as such, itbecomes a more complete tool to explore the mapped scientific field and to find and retrieverelevant information.     

Bibliometric mapping of science in a policy context

Despite the promising introduction of bibliometric maps of science in a science policy context in the nineteen seventies, they have not been very successful yet. It seems, however, that only now they are becoming acknowledged as a useful tool. This is mainly due to the developments and integration of hypertext and graphical interfaces. Because of this, the strength of such navigation tools becomes obvious. The communication through the Internet enables the field expert (as a kind of peer review) as well as the user (from a science policy context) to contribute to the quality of the map and the interface. Moreover, the interface can provide suggestions to answer policy-related question, which is the initial purpose of such maps.     

Tracking techno-science networks: A case study of fuel cells and related hydrogen technology R&;D in Norway

This study explores boundary-crossing networks in fuel-cell science and technology. We use the case of Norwegian fuel cell and related hydrogen research to explore techno-science networks. Standard bibliometric and patent indicators are presented. Then we explore different types of network maps — maps based on co-authorship, co-patenting and co-activity data. Different network configurations occur for each type of map. Actors reach different levels of prominence in the different maps, but most of them are active both in science and technology. This illustrates that to appreciate fully the range of science-technology interplay, all three analyses need to be taken into account.     

Mapping the social and behavioral sciences world-wide: Use of maps in portfolio analysis of national research efforts

We have developed a method to identify and map the internationally most visible research topics occurring in the social and behavioral sciences, as well as the topics which changed most over a decade. Methods and data relevent to a portfolio analysis of national research efforts are described. Keywords used by authors in scientific or scholarly publications provide a window on scientific developments and changes in scientific research. Using an interdisciplinary database, the SSCI, developments in publications were traced world-wide and for the US, UK, France, Germany, and the Netherlands. We compared two periods: 1981–85 and 1986–90 We discuss the major substantive developments occurring during 1981–1990, as visible in maps depicting both topics and disciplines. It is shown that the maps, enriched with scientometric indicators of strengths and weaknesses of national research efforts, can be important tools for science policy. The findings indicate that the research front on many topics in both social and behavioral sciences is international in the late 1980s.     

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 easy-to-interpret way. The paper consists of three parts. In the first part, an overview of VOSviewer’s functionality for displaying bibliometric maps is provided. In the second part, the technical implementation of specific parts of the program is discussed. Finally, in the third part, VOSviewer’s ability to handle large maps is demonstrated by using the program to construct and display a co-citation map of 5,000 major scientific journals.     

Bibliometric cartography of scientific and technological developments of an R & D field

This paper presents the results of an exploration of bibliometric mapping as an analytic tool to study the important aspects of the relation between science and technology, in particular the science base of technology. We discuss a bibliometric (in particular a publication- and patent-based) approach to develop a cartography of science and technology, i.e., the construction of geometrically organized maps in order to visualize the changing internal structure of science and technology. These maps are based on co-occurrences of publication and patent keywords. We focus on a specific R & D field: optomechatronics. This field is characterized by a strong knowledge transfer between science and technology. We constructed maps for both the science as well as the technology side. Comparison of these two allows the exploration of existing or possible interaction of scientific and technological developments. We identified related subfields (co-word clusters) in the maps of both sides in order to illustrate the interaction between science and technology. Subsequently, we extended the information given by the maps with information on the role and position of a number of countries in the different subfields of optomechatronics, both at the science side as well as at the technology side. This is done by identification of actors in the subfields represented by word clusters in the maps. Cartography of science and technology allows the observation of the structure (and its changes) of scientific and technology fields. Moreover, it illustrates both existing as well as possible links between science and technology. It therefore presents a powerful tool for science, technology and R & D policy.Paper presented at the Fourth International Conference on Bibliometrics, Informetrics and Scientometrics in Berlin (Germany), September 11–15, 1993.     

A scientometric cognitive study of neural network research: Expert mental maps versus bibliometric maps

This paper reports on a quantitative analytical methodology which deals with perceptions of scientific experts regarding the intellectual shape and contents (cognitive structure) of their scientific domain. This study examines the method's utility for studying expert views in general, and, more specifically, its strengths and weaknesses as a tool for improving validation studies of bibliometric maps involving subject experts. The main premise is that expert views are based on their internal knowledge structures (mental schemes) of which relevant features can be captured in quantitative data. This approach allows a rigorous and systematic way of studying mental schemes across subject experts. Spatial representations of their data (mental maps) provide insight in properties underlying those knowledge structures. Data from different experts are reconciled to construct a common mental map which displays a group view. This study includes a test to establish the validity of individual mental maps and common mental maps. The methodology is applied to the views of 14 researchers in the field of neural network research and related areas. Key-findings are: (i) mental maps can provide valid representations of expert mental schemes, (ii) experts sharing the same subject field are more likely to share views, (iii) expert judgements of bibliometric maps are affected by the structure of their own mental schemes, as well as (iv) by their views regarding the utility of those maps, and (v) common mental maps and a bibliometric co-word map based on the same set of items differ significantly, showing a resemblance on main features only.     

Applications for bibliometric research in the emerging digital libraries

Large numbers of research documents have recently become available on the Internet through “digital libraries”, and these collections are seeing high levels of use by their related research communities. A secondary use for these document repositories and indexes is as a platform for bibliometric research. We examine the extent to which the new digital libraries support conventional bibliometric analysis, and discuss shortcomings in their current forms. Interestingly, these electronic text archives also provide opportunities for new types of studies: generally the full text of documents are available for analysis, giving a finer grain of insight than abstract-only online databases; these repositories often contain technical reports or pre-prints, the “grey literature” that has been previously unavailable for analysis; and document “usage” can be measured directly by recording user accesses, rather than studied indirectly through document references.     

Future publication success in science is better predicted by traditional measures than by the <Emphasis Type="Italic">h</Emphasis> index

Although the use of bibliometric indicators for evaluations in science is becoming more and more ubiquitous, little is known about how future publication success can be predicted from past publication success. Here, we investigated how the post-2000 publication success of 85 researchers in oncology could be predicted from their previous publication record. Our main findings are: (i) Rates of past achievement were better predictors than measures of cumulative achievement. (ii) A combination of authors’ past productivity and the past citation rate of their average paper was most successful in predicting future publication success (R ² ≈ 0.60). (iii) This combination of traditional bibliographic indicators clearly outperformed predictions based on the rate of the h index (R ² between 0.37 and 0.52). We discuss implications of our findings for views on creativity and for science evaluation.     

Computer-modelled deformation mechanism maps for hot uniaxially pressed Bi-2223 superconductor

A deformation mechanism map represents the densification behaviour of a green powder body. A map is created by evaluating the rate-equations for five types of densification mechanisms: yield, boundary diffusion, volume diffusion, power-law creep, and Nabarro–Herring creep. These rates are summed where appropriate and integrated to give the density at a given pressure, temperature and time; this can then be plotted on a map. Such maps have been created for hot-pressed Bi-2223, using the HIP 6.0 computer software. Four temperature–density deformation maps were created at different pressing pressures and for two types of powder: a solid-state reacted powder and a pyrolysed organic precursor powder. The resulting maps are compared and discussed in relation to a set of experimental results. This revised version was published online in November 2006 with corrections to the Cover Date.     

Multiparametric characterization of scientometric performance profiles assisted by neural networks: a study of Mexican higher education institutions

Development of accurate systems to assess academic research performance is an essential topic in national science agendas around the world. Providing quantitative elements such as scientometric rankings and indicators have contributed to measure prestige and excellence of universities, but more sophisticated computational tools are seldom exploited. We compare the evolution of Mexican scientific production in Scopus and the Web of Science as well as Mexico’s scientific productivity in relation to the growth of the National Researchers System of Mexico is analyzed. As a main analysis tool we introduce an artificial intelligence procedure based on self-organizing neural networks. The neural network technique proves to be a worthy scientometric data mining and visualization tool which automatically carries out multiparametric scientometric characterizations of the production profiles of the 50 most productive Mexican Higher Education Institutions (in Scopus database). With this procedure we automatically identify and visually depict clusters of institutions that share similar bibliometric profiles in bidimensional maps. Four perspectives were represented in scientometric maps: productivity, impact, expected visibility and excellence. Since each cluster of institutions represents a bibliometric pattern of institutional performance, the neural network helps locate various bibliometric profiles of academic production, and the identification of groups of institutions which have similar patterns of performance. Also, scientometric maps allow for the identification of atypical behaviors (outliers) which are difficult to identify with classical tools, since they outstand not because of a disparate value in just one variable, but due to an uncommon combination of a set of indicators values.     

Web 2.0 and its dimensions in the scholarly world

A bibliometric analysis was performed on a set of 1718 documents relating to Web 2.0 to explore the dimensions and characteristics of this emerging field. It has been found that Web 2.0 has its root deep in social networks with medicine and sociology as the major contributing disciplines to the scholarly publications beyond its technology backbone — information and computer science. Terms germane to Web 2.0, extracted from the data collected in this study, were also visualized to reflect the very nature of this rising star on the Internet. Web 2.0, according to the current research, is of the user, by the user, and more importantly, for the user.     

Correcting glasses help fair comparisons in international science landscape: Country indicators as a function of ISI database delineation

The increasing use of bibliometric indicators in science policy calls for a reassessment of their robustness and limits. The perimeter of journal inclusion within ISI databases will determine variations in the classic bibliometric indicators used for international comparison, such as world shares of publications or relative impacts. We show in this article that when this perimeter is adjusted using a natural criterion for inclusion of journals, the journal impact, the variation of the most common country indicators (publication and citation shares; relative impacts) with the perimeter chosen depends on two phenomena. The first one is a bibliometric regularity rooted in the main features of competition in the open space of science, that can be modeled by bibliometric laws, the parameters of which are “coverage-independent” indicators. But this regularity is obscured for many countries by a second phenomenon, the presence of a sub-population of journals that does not reflect the same international openness, the nationally-oriented journals. As a result indicators based on standard SCI or SCISearch perimeters are jeopardized to a certain extent by this sub-population which creates large irregularities. These irregularities often lead to an over-estimation of share and an under-estimation of the impact, for countries with national editorial tradition, while the impact of a few mainstream countries arguably benefits from the presence of this sub-population. This revised version was published online in August 2006 with corrections to the Cover Date.     

Development of processing maps for a Ni-based superalloy

The hot deformation characteristics of a Ni-based superalloy were studied in the temperature range 1050–1180 °C and strain rate range 0.01–10 s^− 1 using hot compression tests. Processing maps for hot working were developed on the basis of the variations of efficiency of power dissipation with temperature and strain rate, interpreted using a dynamic materials model. A hot deformation equation is given to characterize the dependence of peak stress on the temperature and strain rate. A hot deformation apparent activation energy of the Ni-based superalloy is about 496 kJ/mol. The processing maps of the Ni-based superalloy obtained in a strain range of 0.1–0.7 are essentially similar, which indicates that strain does not have a significant influence. The maps exhibit a clear domain with its peak efficiency at about 1140 °C and 0.01 s^− 1; the domain has its peak efficiency of about 36–41% for different strains. On the basis of hot deformation microstructural observations, the full recrystallization region can be identified in the processing map at a strain of 0.7.     

Mapping scientific institutions

We have developed a set of routines that allows to draw easily different maps of the research carried out in a scientific institution. Our toolkit uses OpenSource elements to analyze bibliometric data gathered from the Web Of Science. We take the example of our institution, ENS de Lyon, to show how different maps, using co-occurrence (of authors, keywords, institutions…) and bibliographic coupling can be built. These maps may become a valuable tool for discussing institutions’ policies, as they offer different views on the institution at a global scale.     

Bibliometric fingerprints: name disambiguation based on approximate structure equivalence of cognitive maps

Authorship identity has long been an Achilles’ heel in bibliometric analyses at the individual level. This problem appears in studies of scientists’ productivity, inventor mobility and scientific collaboration. Using the concepts of cognitive maps from psychology and approximate structural equivalence from network analysis, we develop a novel algorithm for name disambiguation based on knowledge homogeneity scores. We test it on two cases, and the results show that this approach outperforms other common authorship identification methods with the ASE method providing a relatively simple algorithm that yields higher levels of accuracy with reasonable time demands.     

Impact of bibliometrics upon the science system: Inadvertent consequences?

Summary Ranking of research institutions by bibliometric methods is an improper tool for research performance evaluation, even at the level of large institutions. The problem, however, is not the ranking as such. The indicators used for ranking are often not advanced enough, and this situation is part of the broader problem of the application of insufficiently developed bibliometric indicators used by persons who do not have clear competence and experience in the field of quantitative studies of science. After a brief overview of the basic elements of bibliometric analysis, I discuss the major technical and methodological problems in the application of publication and citation data in the context of evaluation. Then I contend that the core of the problem lies not necessarily at the side of the data producer. Quite often persons responsible for research performance evaluation, for instance scientists themselves in their role as head of institutions and departments, science administrators at the government level and other policy makers show an attitude that encourages &apos;quick and dirty&apos; bibliometric analyses whereas better quality is available. Finally, the necessary conditions for a successful application of advanced bibliometric indicators as support tool for peer review are discussed.     

Hot deformation behavior of Ti-15-3 titanium alloy: a study using processing maps,activation energy map,and Zener–Hollomon parameter map

The hot deformation behavior of Ti-15-3 titanium alloy was investigated by hot compression tests conducted in the temperature range 850–1150 °C and strain rate range 0.001–10 s⁻¹. Using the flow stress data corrected for deformation heating, the activation energy map, processing maps and Zener–Hollomon parameter map were developed to determine the optimum hot-working parameters and to investigate the effects of strain rate and temperature on microstructural evolution of this material. The results show that the safe region for hot deformation occurs in the strain rate range 0.001–0.1 s⁻¹ over the entire temperature range investigated. In this region, the activation energy is ~240 ± 5 kJ/mol and the ln Z values vary in range of 13.9–21 s⁻¹. Stable flow is associated with dynamic recovery and dynamic recrystallization. Also, flow instabilities are observed in the form of localized slip bands and flow localization at strain rates higher than 0.1 s⁻¹ over a wide temperature range. The corresponding ln Z values are larger than 21 s⁻¹. The hot deformation characteristic of Ti-15-3 alloy predicted from the processing maps, activation energy map, and Zener–Hollomon parameter map agrees well with the results of microstructural observations.     

International scientific co-operation and awareness within the European community: Problems and perspectives

International scientific co-operation (ISC) and awareness are topics of increasing interest for both scientists and science policy makers. In this paper, we adopt primarily the science policy point of view. After a concise overview of the literature we summarize the main results of the research we conducted. The main outcome with respect to ISC is that it increases. However, large differences exist between countries and between scientific disciplines. ISC and awareness constitute a complex phenomenon, affected by several factors, science-internal, as well as external. In the paper several techniques are described, amongst which those that can visualize ISC relations through analytical maps. An important aspect of our research methodology is the combination of various quantitative, bibliometric analyses and qualitative research on the structure of science and the relations between science and society. Finally, we sketch perspectives for future research.     

Dynamics of a family of continued fraction maps

We explore the dynamics of a 1-parameter family of continued fraction maps of the unit interval. The family contains as special instances the Gauss continued fraction map and the Fibonacci map. We determine the transfer operators of these dynamical maps and prove that the Denjoy–Minkowski measure is a common invariant measure of the family. We show that their analytic invariant measures obey a common functional equation generalizing Lewis’ functional equation and we find a.c. invariant measures for some members of the family. We also discuss a certain involution of this family which sends the Gauss map to the Fibonacci map relating Riemann's zeta function to the so-called Fibonacci zeta function.