The network structure of a hyperlinked environment can be a rich source of information about the content of the environment, provided we have effective means for understanding it. We develop a set of algorithmic tools for extracting information from the link structures of such environments, and report on experiments that demonstrate their effectiveness in a variety of context on the World Wide Web. The central issue we address within our framework is the distillation of broad search topics, through the discovery of “authorative” information sources on such topics. We propose and test an algorithmic formulation of the notion of authority, based on the relationship between a set of relevant authoritative pages and the set of “hub pages” that join them together in the link structure. Our formulation has connections to the eigenvectors of certain matrices associated with the link graph; these connections in turn motivate additional heuristrics for link-based analysis.

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Authoritative sources in a hyperlinked environment

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.

/pdf/software-survey-vosviewer-a-computer-program-for-505jc6bwmd.pdf

Software survey: VOSviewer, a computer program for bibliometric mapping.

A new form of document coupling called co-citation is defined as the frequency with which two documents are cited together. The co-citation frequency of two scientific papers can be determined by comparing lists of citing documents in the Science Citation Index and counting identical entries. Networks of co-cited papers can be generated for specific scientific specialties, and an example is drawn from the literature of particle physics. Co-citation patterns are found to differ significantly from bibliographic coupling patterns, but to agree generally with patterns of direct citation. Clusters of co-cited papers provide a new way to study the specialty structure of science. They may provide a new approach to indexing and to the creation of SDI profiles.

Co-citation in the scientific literature: A new measure of the relationship between two documents

bibliometrix: An R-tool for comprehensive science mapping analysis

We review the recent rapid progress in the statistical physics of evolving networks. Interest has focused mainly on the structural properties of complex networks in communications, biology, social sciences and economics. A number of giant artificial networks of this kind have recently been created, which opens a wide field for the study of their topology, evolution, and the complex processes which occur in them. Such networks possess a rich set of scaling properties. A number of them are scale-free and show striking resilience against random breakdowns. In spite of the large sizes of these networks, the distances between most of their vertices are short - a feature known as the 'small-world' effect. We discuss how growing networks self-organize into scale-free structures, and investigate the role of the mechanism of preferential linking. We consider the topological and structural properties of evolving networks, and percolation and disease spread on these networks. We present a number of models demonstrat...

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Evolution of networks

https://science.sciencemag.org/content/sci/120/3129/1038.full.pdf

Forms for Literature Citations.

As a child I grew up in awe of an English accent. That was not unusual for an American because so many movie stars spoke with an English accent. All during my high school and college days I instinctively believed that anyone who spoke with an Oxford or BBC accent was an authority. And even professors and intellectuals who adopted the Harvard version of an English accent held me in awe. Several of my professors at Columbia University deserved that sort of adulation since they were indeed experts in their respective fields. However, that all changed when I reached Johns Hopkins University in 1951, when I audited a course in statistics with Professor W.G. Cochran. The student who sat next to me was a Brit who spoke with great authority but after a few weeks I began to realize that most of what he said was nonsense. For the next few years I had little contact with Englishmen during my stay at Johns Hopkins but my boss at the Welch Medical Library Indexing Project reminded me regularly that he had studied Elizabethan medicine at Oxford. My next encounter with the English occurred after leaving the Welch Project. I was impressed by the performance of the editor of the Journal of Documentation, who stood up to the harassment from my then former boss. He was angry at me for submitting a paper to the Journal of Documentation without his permission. So much so that he asked the attorney for the university to write a ‘cease and desist’ letter but the editor did not buckle to his threats. So I can honestly say that my first published paper appeared in an English publication [1]. These stressful events occurred while I was enrolled at Columbia University School of Library Service. Of course, even during my two years in Baltimore the British influence on my career was felt strongly. My ‘bible’, so to speak, at that time was the one-volume, 700+ page Proceedings of the 1948 Royal Society Scientific Information Conference [2]. I mentioned the key role played by John Desmond Bernal in that meeting when I spoke about his impact on science policy studies and the field of information science at the recent symposium held at University College in Dublin in September 2007 [3]. Hopefully the Royal Society will soon post the full text of the Royal Society Proceedings to their website. A few years ago I was able to convince the National Academy of Sciences Press to post the full text of the two volumes of the 1958 Proceedings of the International Conference on Scientific Information sponsored by the National Science Foundation [4]. The English connection picked up again in the spring of 1957 when much to my surprise I received an invitation to attend the Dorking Conference on Classification. My brief recollection of that conference follows, with thanks to Robert V. Williams (the co-coordinator of the Pioneers of Information Science Scrapbook [5], which includes my account titled Memories of the 1957 Dorking Conference,

/pdf/how-i-learned-to-love-the-brits-5cy3v0k9ll.pdf

How I learned to love the Brits

The uses of punched‐cards in documentation are already so varied as to confuse the potential user. Consequently, many organizations and individuals who could efficiently employ existing techniques are not aware of these possibilities. Even in the specialized problem of preparing subject‐heading lists various approaches are in use. The purpose of this paper is to outline the uses of punched‐cards in this special area.

The preparation of subject‐heading lists by automatic punched‐card techniques

Maps of research in the sciences and social sciences for the year 19S3 were generated from the Science Citation Indexm /Social Sciences Citation Indexa database using a single-link clustering algorithm. The combined use of fractional citation counting and recitation frequency thresholds ensured a fair representation of smaller areas. The resulting clusters of co-cited publications were aggregated through iterative computer runs at five levels, Cl (Imal) to C5 (global). Multidimensional scaling at each level allowed the matrix of linked publications to be represented geometrically as maps. Each research front or node appears on the maps in proportion to the population (size) of its citing publications. Analyses of the distribution of research fronts by disciplines and nations are demonstrated, ss well ss measures of expectation and immediacy for research in genetic engineering and, in particular, on studies of the beta-thalassemia gene. A walking tour through the maps at various levels coupled with content analyses of linkages reveal that, in general, large central arcaa represent basic research whereas smaffer peripheral specialties represent appfied research. Although in its infancy, the construction of such maps of the sciences (and comparisons of maps over time) holds the potential for a new kind of hktory of science. Each year ISF undertakes an analysiz of a database which is derived from a combination of the Science Citation Index” (SCF ) and the Social Sciences Citation IndeP (SSCP ). The purpose of this analysis is to create what we call maps of science which show the topography of science at various levels of aggregation. These range in scale from a global perspective down to the level of the individual investigator’s key papers. It is fair to say that the science and technology for creating such maps is in its infancy. Earlier work by Garfield, Sher, and Torpie I on his toriographs and Price on networks of scientific papersz showed the longitudinal atnrcture of science by exploiting citation links acroas time. More recent c~citation methods emphasize the cross-sectional structure of science by using c~occurrence of references at a specific point in time, and hence suggest the analogy to geographic maps. The notion that science can be mapped was

/pdf/the-geography-of-science-44ei1jcrjc.pdf

The Geography of Science

/pdf/location-of-milestone-papers-through-citation-networks-4zrn7q01ss.pdf

Eugene Garfield

Papers

Forms for Literature Citations.

How I learned to love the Brits

The preparation of subject‐heading lists by automatic punched‐card techniques

The Geography of Science

Location of Milestone Papers Through Citation Networks