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.

2 1 The innovative transport systems and the CityMobil project 10 1.1 The research questions 10 2 The state of art in the field of automatic transport systems 12 2.1 Case studies and demand studies for innovative transport systems 12 3 The design and implementation of surveys 14 3.1 Definition of experimental design 14 3.2 Questionnaire design and delivery 16 3.3 First analyses on the collected sample 18 4 Calibration of Logit Multionomial demand models 21 4.1 Methodology 21 4.2 Calibration of the “full” model. 22 4.3 Calibration of the “final” model 24 4.4 The demand analysis through the final Multinomial Logit model 25 5 The analysis of interaction between the demand and socioeconomic attributes 31 5.1 Methodology 31 5.2 Application of Mixed Logit models to the demand 31 5.3 Analysis of the interactions between demand and socioeconomic attributes through Mixed Logit models 32 5.4 Mixed Logit model and interaction between age and the demand for the CTS 38 5.5 Demand analysis with Mixed Logit model 39 6 Final analyses and conclusions 45 6.1 Comparison between the results of the analyses 45 6.2 Conclusions 48 6.3 Answers to the research questions and future developments 52

The European commission

Social Network 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...

/pdf/evolution-of-networks-27h4ny8xbi.pdf

Evolution of networks

The Study of Man. By Michael Polanyi. Price, $1.75. Pp. 102. University of Chicago Press, 5750 Ellis Ave., Chicago 37, 1959. One subtitle to Polanyi's challenging and fascinating book might be The Evolution and Natural History of Error , for Polanyi is at pains to expunge what he believes to be the false notion contained in the contemporary view of science which treats it as an object and basically impersonal discipline. According to Polanyi not only is this a radical and important error, but it is harmful to the objectives of science itself. Another subtitle could be Farewell to Detachment , for in place of cold objectivity he develops the idea that science is necessarily intensely personal. It is a human endeavor and human point of view which cannot be divorced from nor uprooted out of the human matrix from which it arises and in which it works. For a good while

Personal Knowledge: Towards a Post-Critical Philosophy

Social network analysis (SNA) is not a formal theory in sociology but rather a strategy for investigating social structures. As it is an idea that can be applied in many fields, we study, in partic...

/pdf/social-network-analysis-a-powerful-strategy-also-for-the-1v0viv3lp8.pdf

Social network analysis: a powerful strategy, also for the information sciences:

Author cocitation analysis (ACA), a special type of cocitation analysis, was introduced by White and Griffith in 1981. This technique is used to analyze the intellectual structure of a given scientific field. In 1990, McCain published a technical overview that has been largely adopted as a standard. Here, McCain notes that Pearson's correlation coefficient (Pearson's r) is often used as a similarity measure in ACA and presents some advantages of its use. The present article criticizes the use of Pearson's r in ACA and sets forth two natural requirements that a similarity measure applied in ACA should satisfy. It is shown that Pearson's r does not satisfy these requirements. Real and hypothetical data are used in order to obtain counterexamples to both requirements. It is concluded that Pearson's r is probably not an optimal choice of a similarity measure in ACA. Still, further empirical research is needed to show if, and in that case to what extent, the use of similarity measures in ACA that fulfill these requirements would lead to objectively better results In full-scale studies. Further, problems related to incomplete cocitation matrices are discussed.

Requirements for a cocitation similarity measure, with special reference to Pearson's correlation coefficient

Based on the foundation laid by the h -index we introduce and study the R - and AR -indices. These new indices eliminate some of the disadvantages of the h -index, especially when they are used in combination with the h -index. The R -index measures the h -core’s citation intensity, while AR goes one step further and takes the age of publications into account. This allows for an index that can actually increase and decrease over time. We propose the pair ( h , AR ) as a meaningful indicator for research evaluation. We further prove a relation characterizing the h -index in the power law model

/pdf/the-r-and-ar-indices-complementing-the-h-index-3lkk6ba663.pdf

The R- and AR-indices: Complementing the h-index

I Statistics
This part begins with elementary descriptive statistics and elements of probability It continues with a chapter on inferential statistics, including regression, correlation and nonparametric statistics Next, there is a chapter on sampling theory, including overlap problems Part I concludes with a short description of several techniques of multivariate statistics: multiple regression, principal component analysis, multidimensional scaling and cluster techniques
II Operations research and library management
The second part deals with applications of linear programming, including transportation and assignment problems, and basic queueing theory Special attention is paid to book circulation interference
III Citation analysis
Citer motivations, citation networks, bibliographic coupling and co-citation analysis are introduced here Citation measures such as the impact factor are defined This part ends with some science policy applications
IV Informetric models
Informetric models and their relations are studied At the heart of this theory is the dual approach between sources and items giving rise to the definition of Information Production Processes Explanations and applications of the classical informetric laws as well as fitting methods are provided

Introduction to Informetrics: Quantitative Methods in Library, Documentation and Information Science

It is shown that in most practical cases Salton's cosine formula yields a numerical value that is twice Jaccard's index.

Ronald Rousseau

Papers

Social network analysis: a powerful strategy, also for the information sciences:

Requirements for a cocitation similarity measure, with special reference to Pearson's correlation coefficient

The R- and AR-indices: Complementing the h-index

Introduction to Informetrics: Quantitative Methods in Library, Documentation and Information Science

Similarity measures in scientometric research: the Jaccard index versus Salton's cosine formula