Spatial Social Networks Research Articles

Considering baseline homophily when generating spatial social networks for agent-based modelling

Social networks have become an important part of agent-based models, and their structure may have remarkable impact on simulation results. We propose a simple and efficient but empirically based approach for spatial agent-based models which explicitly takes into account restrictions and opportunities imposed by effects of baseline homophily, i.e. the influence of local socio-demography on the composition of one's social network. Furthermore, the algorithm considers the probability of links that depends on geographical distance between potential partners. The resulting network reflects social settings and furthermore allows the modeller to influence network properties by adjusting agent type specific parameters. Especially the parameter for distance dependence and the probability of distant links allow for control of clustering and agent type distribution of personal networks.

The importance of location in contact networks: Describing early epidemic spread using spatial social network analysis

This paper explores methods for describing the dynamics of early epidemic spread and the clustering of infected cases in space and time when an underlying contact network structure is influencing disease spread. A novel method of describing an epidemic is presented that applies social network analysis to characterise the importance of both spatial location and contact network position. This method enables the development of a model of how these clusters formed, incorporating spatial clustering and contact network topology. Based on data from the first 30 days of the 2007 equine influenza outbreak in Australia, clusters of infected premises (IPs) were identified and delineated using social network analysis to integrate contact-tracing and spatial relationships. Clusters identified by this approach were compared to those detected using the space-time scan statistic to analyse the same data. To further investigate the importance of network and spatial location in epidemic spread, kriging by date of onset of clinical signs was used to model the spatio-temporal spread without reference to underlying contact network structure. Leave-one-out cross-validation was used to derive a summary estimate of the accuracy of the kriged surface. Observations poorly explained by the kriged surface were identified, and their position within the contact network was explored to determine if they could be better explained through analysis of the underlying contact network. The contact network was found to lie at the core of a combined network model of spread, with infected horse movements connecting spatial clusters of infected premises. Kriging was imprecise in describing the pattern of spread during this early phase of the outbreak (explaining only 13% of the variation in date of onset of IPs), because early dissemination was dominated by network-based spread. Combined analysis of spatial and contact network data demonstrated that over the first 30 days of this outbreak local spread emanated outwards from the small number of infected premises in the contact network, up to a distance of around 15 km. Consequently, when a contact network structure underlies epidemic spread, we recommend applying a method of spatial analysis that incorporates the network component of disease spread. Linking the spatial and network analysis of epidemics facilitates inference of the methods of disease transmission, providing a description of the sequence of spatial cluster formation.

Layers, Flows and Intersections: Jeronymo Jose de Mello and Artisan Life in Rio de Janeiro, 1840s-1880s

The social history of Rio de Janeiro's artisans is approached using an interdisciplinary methodology based on spatial data (GIS) and concepts of layers, flows, and intersections. Datasets regarding occupation, real property ownership, and slaveholding are intersected and social change experienced by artisans resident in the diverse neighborhoods of the city is analyzed. The story of one tinker in particular is pursued to illustrate the major changes affecting artisans in Rio during the second half of the nineteenth century as well as to illuminate the complex social and economic experiences of common people such as artisans in a new way based on spatial patterns and social networks. The experience of artisans in general was of gradual dispersion into more diverse and poorer neighborhoods as the city center became increasingly dominated by business and retail. This dispersion resulted in a different set of neighbors and changing social and economic environments for most artisans as they lost their hold on traditional zones in the city center.

Nodal Heterolocalism and Transnationalism at the United States‐Canadian Border*

ABSTRACT. Since the late 1990s Wilbur Zelinsky's theory of “heterolocalism’ has provided human geographers and other social scientists with a new approach to analyzing the spatial patterns and ethnic identities of recent immigrants in the United States. Zelinsky's heterolocal model suggests that, to a degree unknown in the past, new migrants in North American cities may choose to settle in widely dispersed places, rather than in more concentrated ethnic enclaves, while maintaining their ethnic identities. This article expands on and critiques prior work on heterolocalism in Oregon by examining the spatial patterns, ethnic and religious identities, and transnational relationships of two recent refugee groups in three urban areas in the Pacific Northwest. Using data from U.S. and Canadian census records, refugee resettlement agency files, survey questionnaires, structured and unstructured interviews, and participant observation with post‐Soviet Russians and Ukrainians in the Vancouver, British Columbia, Seattle, Washington, and Portland, Oregon metropolitan areas, I analyze the spatial patterns and related social networks that define the identities and residential and religious spaces of these groups to test the efficacy of relating heterolocalism and transnationalism across an international boundary.

Spatial social networks

We introduce a spatial cost topology in the network formation model analyzed by Jackson and Wolinsky, Journal of Economic Theory (1996), 71: 44–74. This cost topology might represent geographical, social, or individual differences. It describes variable costs of establishing social network connections. Participants form links based on a cost-benefit analysis. We examine the pairwise stable networks within this spatial environment. Incentives vary enough to show a rich pattern of emerging behavior. We also investigate the subgame perfect implementation of pairwise stable and efficient networks. We construct a multistage extensive form game that describes the formation of links in our spatial environment. Finally, we identify the conditions under which the subgame perfect Nash equilibria of these network formation games are stable.

A Vulnerability Interpretation of the Geography of HIV/AIDS in Ghana, 1986–1995

Ten years after the human immuno-deficiency virus (HIV) was first reported in Ghana, it continues to spread throughout the country following patterns that are rare in other African countries. HIV is seen in twice as many females as males, more frequently in rural than urban regions, and regions with high rates of polygamy have significantly lower rates. The evidence presented in this paper shows that HIV diffusion patterns probably reflect the spatial distribution and social networks of vulnerable social groups. While information-based campaigns are still necessary in the fight against HIV/AIDS, they fail to enable or empower vulnerable people to protect themselves against infection.

The Number of Members as Determining the Sociological Form of the Group. I

The Number of Members as Determining the Sociological Form of the Group. I