Network centralization with the Gil Schmidt power centrality index

Network centralization is a network index that measures the degree of dispersion of all node centrality scores in a network from the maximum centrality score obtained in the network. The Gil Schmidt power centrality index was developed for use in describing the political networks of Mexico, Gil and Schmidt [Gil, J., Schmidt, S., 1996a. The origin of the Mexican network of power. In: International Social Network Conference, Charleston, SC, USA, pp. 22–25; Gil, J., Schmidt, S., 1996b. The political network in Mexico. Social Networks 18, 355–381]. Upper bounds for network centralization, using the Gil Schmidt power centrality index, are derived for networks of fixed order and for when the network is bipartite, such as can arise from two mode data. In each case the networks that have maximum network centralization are described.     

Testing centralization in random graphs

Centrality is an important concept in social network analysis which involves identification of important or prominent actors. Three common definitions of centrality are degree centrality, closeness centrality and betwenness centrality which yield actor indices. By aggregating these actor indices of centrality across actors, we obtain a single group-level index of centralization. In this paper, we consider the problem of testing whether the observed data is likely to have come from a particular kind of centralized structure of a given size, edge probability and extent of centralization. Eight different group-level indices of centralization are used as test statistics of graph centralization. As our graph model, we assume a general blockmodel which allows a rich probabilistic structure. By carrying out a simulation study the performance of the tests is evaluated by comparing their power functions. The results imply that two tests based on degree and four tests based on closeness have high power. In addition, critical values of the tests are modeled conditional on graph parameters via a linear regression model. An application is illustrated with analysis on a real data set.     

Tailoring Organizational Characteristics for Empowerment

ABSTRACT

Empowerment is an important value orientation and intervention approach in social work and other disciplines. Viewed from an ecological perspective, a good fit between organizational characteristics and the life circumstances of individuals should provide empowerment benefits. By studying interaction effects of material resources and organizational characteristics on empowerment, this research sought to extend understanding of empowerment dynamics in community organizations. Using hierarchical regression analyses to investigate socio-economic status (SES) in a moderator model, findings of the study demonstrated that, among a diverse group of participants in two different faith-based community organizations, perceptions of organizational characteristics were more strongly related to empowerment for participants of lower SES. A substantive implication of the study is that community practitioners should attend to the fit between specific organizational processes and economic circumstances of community based organization participants. Strategies weighted toward attention to relationships among members linked to availability of and participation in a variety of organizational roles may be more salient for empowerment of the disadvantaged. Our findings are consistent with an ecological orientation to empowerment, and they add further support to the importance of ecological specificity in empowerment theory.     

Centrality in affiliation networks

This paper discusses the conceptualization, measurement, and interpretation of centrality in affiliation networks. Although centrality is a well-studied topic in social network analysis, and is one of the most widely used properties for studying affiliation networks, virtually all discussions of centrality and centralization have concerned themselves with one-mode networks. Bonacich's work on simultaneous group and individual centralities is a notable exception (Social Networks, 1991, 13, 155–168). I begin by outlining the distinctive features of affiliation networks and describe four motivations for centrality indices in affiliation networks. I then consider properties of some existing centrality indices for affiliation networks, including the relationship between centralities for actors and events in these networks, and present a new conceptualization of centrality that builds on the formal properties of affiliation networks and captures important theoretical insights about the positions of actors and events in these networks. These centralities are then illustrated on Galaskiewicz's data on club and board memberships of a sample of corporate executive officers (Social Organization of an Urban Grants Economy. New York: Academic Press, 1985). The conclusion to this paper discusses strengths and weaknesses of centrality indices when applied to affiliation networks.     

Interorganizational network findings from a nationwide cardiovascular disease prevention initiative

ObjectivesTo use network analysis in order to evaluate the effectiveness of interorganizational networks in implementing policy, systems, and environmental interventions for cardiovascular disease prevention throughout the United States.MethodsEvaluators conducted an interorganizational network (ION) survey to examine information sharing and joint planning within organizational relationships in 15 community-based cardiovascular disease prevention partnership networks. Density and betweenness centrality scores at the node- and network-level were calculated for each partnership network using UCINET© network analysis software. Common data patterns were then extracted using a multiple case study format.ResultsNetwork density scores ranged from 0.50 to 1.00 (M = 0.84, SD = 0.14) for information sharing and 0.43–1.00 (M = 0.77, SD = 0.15) for joint planning. Centralization indices ranged from 0.00 to 0.11 (M = 0.04, SD = 0.03), and 0.00-0.17 (M = 0.06, SD = 0.05), respectively. Overall, 73.33 % of communities were successful in meeting their partnership goals.ConclusionsWhen planning and implementing interorganizational networks, high betweenness centrality and more hierarchically structured networks were identified as the most salient partnership characteristics to programmatic success. The network findings were triangulated with previously published qualitative data to provide context. These findings provide valuable insight on how national networks can be designed and leveraged to implement systematic community health projects.     

Network centrality and social movement media coverage: A two-mode network analytic approach

This article examines the relationship between structural location (namely, degree centrality) and news media coverage. Our central hypothesis is that the network centrality of social movement actors is positively associated with the prevalence of actors being cited in the print news media. This paper uses two-mode data from a communication network of environmentalists in British Columbia, and examines the relationship between their structural location and the frequency by which they are cited in newsprint media with regard to particular frames (about forest conservation, environmental protest, and related issues). We asked a sample of social movement participants about their ties to a target list of relatively high profile actors (environmental activists). We turned the resulting network matrix into a bipartite graph that examined the relationships amongst the target actors vis a vis the respondents. Next we calculated point in-degree for the target actors. For the target actors we also have data from a representative sample of 957 print news articles about forestry and conservation of old growth forests in British Columbia. We compare the effects of network centrality of the target actor versus several attributes of the target actors (gender, level of radicalism, leadership status) on the amount of media coverage that each of the target actors receives. We find that network centrality is associated with media coverage controlling for actor attributes. We discuss theoretical implications of this research. Finally, we also discuss the methodological pros and cons of using a “target name roster” to construct two-mode data on social movement activists.     

Structural effects of network sampling coverage I: Nodes missing at random

Network measures assume a census of a well-bounded population. This level of coverage is rarely achieved in practice, however, and we have only limited information on the robustness of network measures to incomplete coverage. This paper examines the effect of node-level missingness on 4 classes of network measures: centrality, centralization, topology and homophily across a diverse sample of 12 empirical networks. We use a Monte Carlo simulation process to generate data with known levels of missingness and compare the resulting network scores to their known starting values. As with past studies (0035 and 0135), we find that measurement bias generally increases with more missing data. The exact rate and nature of this increase, however, varies systematically across network measures. For example, betweenness and Bonacich centralization are quite sensitive to missing data while closeness and in-degree are robust. Similarly, while the tau statistic and distance are difficult to capture with missing data, transitivity shows little bias even with very high levels of missingness. The results are also clearly dependent on the features of the network. Larger, more centralized networks are generally more robust to missing data, but this is especially true for centrality and centralization measures. More cohesive networks are robust to missing data when measuring topological features but not when measuring centralization. Overall, the results suggest that missing data may have quite large or quite small effects on network measurement, depending on the type of network and the question being posed.     

Organizational Linkages among the Inner Group of the Capitalist Class

Abstract

This study investigates the non-corporate organizational linkages among the inner group of the capitalist class, defined as those who are interlocked with three or more corporations. To the extent that persons already linked through corporate ties also are connected through common memberships in business organizations, social clubs, and other voluntary organizations, the likelihood of a national cohesive power elite is increased. The corporate data used are from the 1976 government study of the 130 major companies in the United States, controlling collectively 25 percent of all assets. The biographical data on the 66 individuals found to sit on three or more boards among these 130 companies were taken from Who's Who. Several key organizations were found where the members of the elite were especially interconnected. A cluster of 15 individuals with 13 or more common memberships within the 66 were identified as having the greatest linkages. The analysis of the number of common links for each possible pair among these 15 individuals revealed an average of 2.76. Moreover, one-third of the 15 had four links or more, with at least five persons among this inner circle, revealing the nucleus of the inner group. These data show that there is a social network, national in scope, which provides a basis for unity among leaders of the capitalist class.     

Centrality in social networks conceptual clarification

The intuitive background for measures of structural centrality in social networks is reviewed and existing measures are evaluated in terms of their consistency with intuitions and their interpretability.Three distinct intuitive conceptions of centrality are uncovered and existing measures are refined to embody these conceptions. Three measures are developed for each concept, one absolute and one relative measure of the centrality of positions in a network, and one reflecting the degree of centralization of the entire network. The implications of these measures for the experimental study of small groups is examined.     

Computer Diffusion and Worker Empowerment

Abstract

Much anecdotal material describes various human impacts of computer adoption within the social work profession, however, there is scant research which confirms or challenges these assumptions. This article describes a study which investigates the diffusion of computers into the social work profession in terms of empowerment as an individual outcome for workers. A questionnaire returned by 520 social workers provided data on organizational computer diffusion, organizational centralization, and the Social Worker Empowerment Scale. Workers in organizations where computer diffusion was more advanced, and those in more decentralized decisionmaking environments were found to be more empowered.     

Talking War: How Elite U.S. Newspaper Editorials and Opinion Pieces Debated the Attack on Iraq

Abstract

This paper examines how elite newspaper editorials and opinion pieces (hereafter collectively called op-eds) debated the attack on Iraq. The period examined was the two months preceding Congress's October 2002 authorization of the use of force against Iraq. The 292 op-ed pieces examined represent one of the most extensive looks at such op-ed activity in the United States.

There were several major findings. First, contrary to some liberal charges, the commentary overall was more critical than supportive of the administration. On the other side, however, if the elite press was not slavishly supportive of U.S. foreign policy, its criticisms were also rather muted. Supported therefore is the view that the elite media keep respectable opinion on foreign policy within a narrow range that excludes the most damaging criticism. Most notably missing from the print debate on Iraq in this period was much objection to the attack on specifically legal or moral grounds. The avoidance by the elite press of legal and moral language arguably helped convey the general impression that no legal or moral considerations were at stake. At the very least, it is shown, this sector of the public sphere did little to help the nation as a whole to deliberate morally about war.     

The duality of world cities and firms: comparing networks,hierarchies, and inequalities in the global economy

Much of the research on globalization conceives of the global economy as structured by networks among places, while separately organizational research has examined the role of networks among firms in structuring competition, collaboration, and cooperation. In both cases, position and centrality within the network confers certain advantages and disadvantages, the distribution of which defines a hierarchy. In this article, I explore the idea of dual networks of world cities and firms, then use Breiger's approach to define two such networks: one among 313 world cities, another among 100 advanced producer service firms. Comparison of the degree of inequality in the hierarchies implied by these networks suggest that world city hierarchies are steeper than firm hierarchies (that is there is greater inequality among cities). Thus, even under conditions of footloose global capitalism, place still matters: where a producer is located has more impact than who provides support services.     

Authentic leadership and its influence on group cohesion and organizational identification: the role of organizational justice as a mediating variable / El liderazgo auténtico y su influencia sobre la cohesión grupal y la identificación organizacional: el papel de la justicia organizacional como variable mediadora

Abstract

The aim of this study is to analyse the relationship between authentic leadership, group cohesion, organizational identification and the potential effect of organizational justice as a mediating variable. Partial Least Squares (PLS) modelling was used to analyse the data from 210 employees at several Spanish companies. The results showed that organizational justice as a mediator in the proposed model and positive relationships among the variables studied. These findings are discussed taking into account the importance of the authentic leadership model in the study of group processes in organizations and the development of policies and behaviours that promote ethics, transparency and justice in companies.     

Categorical attribute based centrality: E–I and G–F centrality

In a paper examining informal networks and organizational crisis, Krackhardt and Stern (1988) proposed a measure assessing the extent to which relations in a network were internal to a group as opposed to external. They called their measure the E–I index. The measure is now in wide use and is implemented in standard network packages such as UCINET ( Borgatti et al., 2002). The measure is based on a partition-based degree centrality measure and as such can be extended to other centrality measures and group level data. We explore extensions to closeness, betweenness and eigenvector centrality, and show how to apply the technique to sets of subgroups that do not form a partition. In addition, the extension to betweenness suggests a linkage to the Gould and Fernandez brokerage measures, which we explore.     

The rise and fall of collective identity in networked movements: communication protocols,Facebook, and the anti-Berlusconi protest

This paper explores the impact of communication protocols on the development of collective identity in networked movements. It focuses primarily on how communication protocols change patterns of interactions and power relationships among the constituents of social movements. The paper suggests that the communication protocols of commercial social networking media lead to organizational centralization and fragmentation in social movements by eroding one of the preconditions of collective identity, namely solidarity. The empirical material presented is part of a PhD dissertation on a political protest movement and their use of Facebook as a core communication and organizational platform. The data gathering is multi-methodological and relies on both qualitative and quantitative data collection techniques in the form of a historical analysis of interaction patterns, and a content analysis of online conversations among activists.     

Integrating Sexual Health Services Into Primary Care: An Overview of Health Systems Issues and Challenges in Developing Countries

ABSTRACT

Current attempts to address the high burden of sexual health morbidity and mortality in developing countries remain limited in scale due to a range of health system constraints. We conducted a literature review of the policy and programmatic issues that influence the integration of sexual health into primary care services in developing countries. Forty-seven reports were identified from a search of both peer-reviewed and gray literature. Key issues identified were intersectoral and intergovernmental coordination; management and organizational issues including decentralization, health sector reform, logistics, and referral systems; human resources, including training and support required to increase service scope; relationships between the public and private sectors; and scaling-up and financing issues.     

Seeing the Same Thing Differently: Program Director,Faculty, and Student Perceptions of MSW LGBT Competence

ABSTRACT

This exploratory study examined MSW education’s organizational-level lesbian, gay, bisexual, and transgender (LGBT) competence. Data were gathered from a sample of MSW program directors, faculty members, and students (N=1385) from 34 MSW programs in the United States. Hierarchical linear modeling analyzed differences in perceptions of organizational LGBT competence between MSW programs and among participants in the same program. Results showed organizational LGBT competence varied significantly among MSW programs and indicated program directors, faculty members, and students had different perceptions of the competence of their shared program. Specifically, directors rated the LGBT competence of their program higher than faculty, and faculty rated their program higher than students did. Implications for research and suggestions for social work education are discussed.     

Network Composition,Social Integration,and Sense of Coherence in Chinese American Young Adults

Summary

This investigation examined the network composition, social integration, and sense of coherence in a group of 353 Chinese American students at a public university. About half (55.5%) of the sample had a Chinese-only (ethnically same) network while the remainder had either ethnically and/or racially mixed networks. Late immigrants (arriving after age 12) were more likely to have close relationships with other Chinese only, and American-borns and early immigrants (arriving before or at age 12) were more likely to have non-Chinese Asian and non-Asian members in their network. Greater racial/ ethnic similarity among network members was associated with greater network integration. Individuals with a racially/ethnically mixed network enjoyed the highest sense of coherence, followed by those with an ethnically same network, and those with either a racially-same or mixed network reported the lowest sense of coherence. Altogether, the findings suggest ethnically/racially similar networks afford a sense of comfort, but more diverse networks offer the reward of increased competence and better person-environment fit.     

Help Seeking and Treatment Use Among Suicidal College Students

Abstract

Objectives: Many suicidal college students do not receive mental health treatment, and the reasons for this are not fully understood. This study examines how attitudes, beliefs, and social network factors relate to help seeking among suicidal students. Participants: A random sample of 8,487 undergraduate and graduate students from 15 US universities participated. Methods: A Web-based survey administered in spring 2009 examined correlates of mental health service utilization among students reporting serious thoughts of suicide in the previous year (n = 543). Results: Correlates of treatment use included perceived need, beliefs that treatment is effective, contact with service users, lower personal stigma, higher perceived stigma, fewer positive relationships, and sexual minority or Caucasian identity. Conclusions: Help seeking among suicidal students is associated with a range of personal and social network factors. Campus strategies to enhance help seeking should be tailored to address identified facilitators and barriers to treatment use among target populations.     

Outcomes of ITV and Face-to-Face Instruction in a Social Work Research Methods Course

ABSTRACT

The heart of social work is relationship. IVT literature implies obstacles to interaction, but overlooks the centrality of relationship and challenges in distance education for teaching and modeling social work relationships. This article addresses how to ensure in the moderately-sized (40 students) IVT classroom that relationship remains integral to effective social work practice.