Abstract: Using computer databases of scientific papers in physics, biomedical research, and computer science, we have constructed networks of collaboration between scientists in each of these disciplines. In these networks two scientists are considered connected if they have coauthored one or more papers together. Here we study a variety of nonlocal statistics for these networks, such as typical distances between scientists through the network, and measures of centrality such as closeness and betweenness. We further argue that simple networks such as these cannot capture variation in the strength of collaborative ties and propose a measure of collaboration strength based on the number of papers coauthored by pairs of scientists, and the number of other scientists with whom they coauthored those papers.

Abstract: Using computer databases of scientific papers in physics, biomedical research, and computer science, we have constructed networks of collaboration between scientists in each of these disciplines. In these networks two scientists are considered connected if they have coauthored one or more papers together. We study a variety of statistical properties of our networks, including numbers of papers written by authors, numbers of authors per paper, numbers of collaborators that scientists have, existence and size of a giant component of connected scientists, and degree of clustering in the networks. We also highlight some apparent differences in collaboration patterns between the subjects studied. In the following paper, we study a number of measures of centrality and connectedness in the same networks.

Abstract: A field study involving 190 employees in 38 work groups representing five diverse organizations provided evidence that social networks, as defined in terms of both positive and negative relations, are related to both individual and group performance. As hypothesized, individual job performance was positively related to centrality in advice networks and negatively related to centrality in hindrance networks composed of relationships tending to thwart task behaviors. Hindrance network density was significantly and negatively related to group performance.

Abstract: We study a problem of data packet transport in scale-free networks whose degree distribution follows a power law with the exponent $\ensuremath{\gamma}$. Load, or ``betweenness centrality,'' of a vertex is the accumulated total number of data packets passing through that vertex when every pair of vertices sends and receives a data packet along the shortest path connecting the pair. It is found that the load distribution follows a power law with the exponent $\ensuremath{\delta}\ensuremath{\approx}2.2(1)$, insensitive to different values of $\ensuremath{\gamma}$ in the range, $2l\ensuremath{\gamma}\ensuremath{\le}3$, and different mean degrees, which is valid for both undirected and directed cases. Thus, we conjecture that the load exponent is a universal quantity to characterize scale-free networks.

Abstract: The metabolic network of the catabolic, energy and biosynthetic metabolism of Escherichia coli is a paradigmatic case for the large genetic and metabolic networks that functional genomics efforts are beginning to elucidate. To analyse the structure of previously unknown networks involving hundreds or thousands of components by simple visual inspection is impossible, and quantitative approaches are needed to analyse them. We have undertaken a graph theoretical analysis of the E. coli metabolic network and find that this network is a small-world graph, a type of graph distinct from both regular and random networks and observed in a variety of seemingly unrelated areas, such as friendship networks in sociology, the structure of electrical power grids, and the nervous system of Caenorhabditis elegans. Moreover, the connectivity of the metabolites follows a power law, another unusual but by no means rare statistical distribution. This provides an objective criterion for the centrality of the tricarboxylic acid cycle to metabolism. The small-world architecture may serve to minimize transition times between metabolic states, and contains evidence about the evolutionary history of metabolism.

Abstract: This article presents the Internet Connectedness Index (ICI), a measure for monitoring long-term inequalities in the quality of Internet connections among users, especially in terms of whether Internet connections will enhance the chances of people's upward mobility. This index is preferable to more established digital divide measures (e.g., gadgetry ownership or time online) for research on how the Internet is being incorporated into a world of structural inequalities. The ICI utilizes conventional time, history, and context measures, but goes beyond them to capture the scope and centrality of Internet incorporation into the everyday lives of diverse social groups. The validity and robustness of ICI vis-a-vis conventional ownership and time online measures are demonstrated in this article. In addition, the authors discuss theoretical, methodological, and policy implications based on the results. The analytical data are drawn from the Communication Technology and Community Program's Metamorphosis Project,...

Abstract: Using a combination of domain names and user counts, this article provides an assessment of the global distribution of Internet content creation at the national and urban levels and the structure of the supply and demand for this content at the national level. Theories of export-based development are used to assess the strengths and weaknesses of countries' Internet presence and the ramifications of this for future development.

Abstract: The energy and centrality dependence of the charged multiplicity per participant nucleon is shown to be able to differentiate between final state saturation and fixed scale perturbative QCD models of initial entropy production in high-energy heavy-ion collisions. The energy dependence is shown to test the nuclear enhancement of the minijet component of the initial conditions, while the centrality dependence provides a key test of whether gluon saturation is reached at RHIC energies. The HIJING model predicts that the rapidity density per participant increases with centrality, while the saturation model prediction is essentially independent of centrality.

Abstract: It proposes a model about the cognitive structure of work meaning that is composed by 4 facets: work centrality, value attributes (what must work be), descriptive attributes (what is work), and the hierarchy of attributes. The descriptive and value attributes are considered from their factor structures. To evaluate the empiric support of this model and to explore the existing relations among the referred facets, a study was developed with 622 employees in a dwelling building firm and two supermarket chains, applying structured questionnaire, in two versions (with the use of non-verbal resources), in conformity to educational level. Regression analyses were developed, that among other aspects, they show the independency of work centrality and the complexity of the relationship among the factors of value and descriptive attributes. The development of cluster analyses with a set of scores in the four facets show six patterns of work meaning, which are shared among the sample segments. The modal pattern is characterized for attribution of high work centrality and by articulating economic values (of the of life) with expressive values (success and personal realization). By end, discuss about the proposed model and the found results, indicating the ways in which can be useful in the manager of persons.

Abstract: Social studies researchers use graphs to model group activities in social networks. An important property in this context is the centrality of a vertex: the inverse of the average distance to each other vertex. We describe a randomized approximation algorithm for centrality in weighted graphs. For graphs exhibiting the small world phenomenon, our method estimates the centrality of all vertices with high probability within a (1 + ∈) factor in near-linear time.

Abstract: 1. Introduction Had I been more clever, and had the editors allowed it, this paper would appear entirely as marginalia, or at least with the more important points off in the margins, as in (1), where the ideal format for this paper is given:

Abstract: This article analyses South Africa's unsuccessful bid to host the 2006 FIFA World Cup. A discussion of the bid's leading organizers, corporate sponsors, and marketing tactics provides the basis for a critical examination of the policy and philosophy behind the bid campaign. In doing so, the author critiques the World Cup's projected costs and benefits and assesses the tournament's impact on the distribution of wealth in post-apartheid South Africa. This local case study sheds light on football's economic and political centrality in contemporary African societies and identifies South Africa's unusual place in football's world marketplace.

Abstract: As an important concept of urban geography, urban centrality means the relative importance of a city as the provider of central goods and service in excess of the needs of its own residents. The concept of centrality is widely used in the study of cities system. But in China, there are some mistakes in the application of centrality for the lack of no special study. In view of this, the paper gives a thorough clarification to urban centrality and does a case study on the cities system of China. The paper firstly clarifies the concept of centrality, and gives a review to the theory studies of it home and abroad. After a brief comparison to the study methods of centrality, this paper selects the employment personnel as the measurement of urban centrality and constructs a series of centrality index system including 9 items based on China's statistical datum in 1997. By the method of the smallest demand quantity, the paper calculates the centrality index of each industry, then works out the general centrality index of 223 cities through factor analysis. According to the results, China center cities are divided into five degrades, which are national cities, regional cities, provincial cities, etc.

Abstract: A number of recent studies have focused on the statistical properties of networked systems such as social networks and the World-Wide Web. Researchers have concentrated particularly on a few properties which seem to be common to many networks: the small-world property, power-law degree distributions, and network transitivity. In this paper, we highlight another property which is found in many networks, the property of community structure, in which network nodes are joined together in tightly-knit groups between which there are only looser connections. We propose a new method for detecting such communities, built around the idea of using centrality indices to find community boundaries. We test our method on computer generated and real-world graphs whose community structure is already known, and find that it detects this known structure with high sensitivity and reliability. We also apply the method to two networks whose community structure is not well-known - a collaboration network and a food web - and find that it detects significant and informative community divisions in both cases.

Abstract: Following the thought of Wellman, we are trying to examine how social relationships within the cyber-community differ from those in the real world. For general internet users, we are also interested in whether their behavior of making friends on the internet is similar to that when off-line? In our findings, it would appear that a pair of friends has the same types of interactions when on the internet as those demonstrated in the real world. We also find that behind an on-line intimate tie with high interaction frequency, there exists a high probability of finding a person with a high degree of centrality within friendship networks in the real world. Our findings do not deny the possibility that there is a large group of ”disembodied” internet users. But for an average user, life in cyberspace is not in large contrast to their real daily life.

Abstract: (2001). The Centrality of Jerusalem to an End of Conflict Agreement. Journal of Palestine Studies: Vol. 30, No. 3, pp. 82-87.

Abstract: This paper uses social network principles to explain the sources of and variations in relationships among health care providers and patients. General principles of social networks applied are global structure, structural equivalence, structural conduciveness, and the duality of network linkages. Specific principles employed to understand structural variability in provider interrelationships are structural encapsulation and structural excludability, centrality and integration, subgroups and structural holes, close ties versus weak ties, and the virtual ties created by computersupported social networks (CSSNs). Various ways that social network principles help explain the evolving complexities of interconnectedness among health care providers and patients are demonstrated. Practical advantages of using social network principles to organize and to manage interrelationships among health care providers and patients are discussed.

Abstract: This paper examines the network of personal contacts, created by interlocking directorates, among all board members of the Top 500 publicly listed Australian companies. In the past it has been difficulty to analyse such sparse networks, however recent advances in our understanding of the 'small world' phenomenon and the application of random graph theory to large networks provide new tools to measure the connectivity of large networks of this type. The paper analyses the 'small world' of Australian company directors in 1976 and 1996. We find that the size of the network increases significantly from 1976 to 1996 and that its connectivity increases also. We examine the most central persons in the network. We find that network centrality differs markedly when measured by average distance rather than degree (i.e. direct contacts) and we examine the network profiles of persons who rank highly on the different scores.

Abstract: The social structural and cultural bases of power in mental health services and social services delivery systems are considered from both social exchange and institutional perspectives. From the point of view of exchange theory, service organizations derive influence from their centrality in local resource exchange networks. Institutionalists point to organizational legitimacy as a main source of organizational influence. They assume that identification with the medical profession and with a psychiatric treatment ideology are powerful legitimating processes. Data are used from 96 organizations, members of service delivery systems in three communities (Bruges, Ghent, and Zeeland, Flanders) to predict dyadic power and overall regional power. Organizational power is derived from centrality in the client referral network and identification with a psychiatric treatment ideology. 4 Tables, 1 Figure, 36 References. Adapted from the source document.

Abstract: This volume is in recognition and appreciation of a political scientist whose work over 30 years has provided some of the key concepts with which we interpret German politics. To have compiled the volume without an underlying purpose, however, would be alien to the man we seek to celebrate. Accordingly, we have set out to employ the intellectual legacy of Gordon Smith in an evaluation of contemporary German politics and government. The legacy can be encapsulated in the concept of ‘the politics of centrality’ in which a centre-oriented party system provides the foundation for a model of party governance geared to a pragmatic search for consensual solutions. In this volume we evaluate the sustainability of the politics of centrality in the face of countervailing tendencies towards bipolarity in the post-Kohl party system. Second, we examine changes taking place in the German model of consensus governance as it confronts the challenges of globalisation, asking whether consensual governance is still – as it has been for Gordon Smith – the ‘efficient secret’ of German politics. Finally – and this is an important issue for someone who has lived a professional and personal life between the United Kingdom and Germany – we assess the potential for reciprocal policy learning between the two countries as the German model adapts to the new international environment. At the general level, Gordon Smith’s legacy lies in the distinctive approach that he brings to bear on the study of German politics. The approach is composed of three elements. First there is the attempt to ‘get inside’ the politics and political culture of the country. This began with a national service posting to a war-ravaged Hamburg in 1945, where he began to rethink his wartime prejudices about the country and its people. Thereafter, understanding Germany became ‘a continuing quest’, sustained by dinner table seminars with his first wife – a Berlinerin with a deep love of German history and culture. A second vital element in his approach is the perspective of comparative politics, which, as Hayward shows in this volume, is essential to an understanding of a nation’s politics. The final ingredient in Gordon Smith’s perspective on politics reflects his early interest in sociology. His linkage between culture and institutions prefigures

Abstract: Fuzzy Cognitive Maps (FCMs) is an Artificial Neural Networks technique that incorporates ideas from Fuzzy Logic, to create a Decision Support System. Using this strucrure we develop a qualitative model of the relationships that exist in the field of political decisions in the case of “Great Albania”. The model that is constructed is examined statically using graph theory techniques to identify the direct vicious or virtuous cycles of the decision process. Additionally graph ‘s density and the conceptual centrality of model’s concepts are calculated. The dynamical behavior of the model is studied through computer simulations and conclusions are drawn for decisions to be taken. The role of Greece in the case of “Great Albania” is examined and possible ways are identified that make FCM an important and useful tool for the decision makers. Conclusions are drawn for the use of FCM as a decision support system for political decisions in general.