Browsing by Author "Moody, James"

Now showing 1 - 6 of 6
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    Comparing transmission potential networks based on social network surveys, close contacts and environmental overlap in rural Madagascar.
    (Journal of the Royal Society, Interface, 2022-01-12) Kauffman, Kayla; Werner, Courtney S; Titcomb, Georgia; Pender, Michelle; Rabezara, Jean Yves; Herrera, James P; Shapiro, Julie Teresa; Solis, Alma; Soarimalala, Voahangy; Tortosa, Pablo; Kramer, Randall; Moody, James; Mucha, Peter J; Nunn, Charles
    Social and spatial network analysis is an important approach for investigating infectious disease transmission, especially for pathogens transmitted directly between individuals or via environmental reservoirs. Given the diversity of ways to construct networks, however, it remains unclear how well networks constructed from different data types effectively capture transmission potential. We used empirical networks from a population in rural Madagascar to compare social network survey and spatial data-based networks of the same individuals. Close contact and environmental pathogen transmission pathways were modelled with the spatial data. We found that naming social partners during the surveys predicted higher close-contact rates and the proportion of environmental overlap on the spatial data-based networks. The spatial networks captured many strong and weak connections that were missed using social network surveys alone. Across networks, we found weak correlations among centrality measures (a proxy for superspreading potential). We conclude that social network surveys provide important scaffolding for understanding disease transmission pathways but miss contact-specific heterogeneities revealed by spatial data. Our analyses also highlight that the superspreading potential of individuals may vary across transmission modes. We provide detailed methods to construct networks for close-contact transmission pathogens when not all individuals simultaneously wear GPS trackers.
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    Epidemic potential by sexual activity distributions.
    (Netw Sci (Camb Univ Press), 2017-12) Moody, James; Adams, Jimi; Morris, Martina
    For sexually transmitted infections like HIV to propagate through a population, there must be a path linking susceptible cases to currently infectious cases. The existence of such paths depends in part on thedegree distribution.Here, we use simulation methods to examine how two features of the degree distribution affect network connectivity: Mean degree captures a volume dimension, while the skewness of the upper tail captures a shape dimension. We find a clear interaction between shape and volume: When mean degree is low, connectivity is greater for long-tailed distributions, but at higher mean degree, connectivity is greater in short-tailed distributions. The phase transition to a giant component and giant bicomponent emerges as a positive function of volume, but it rises more sharply and ultimately reaches more people in short-tail distributions than in long-tail distributions. These findings suggest that any interventions should be attuned to how practices affect both the volume and shape of the degree distribution, noting potential unanticipated effects. For example, policies that primarily affect high-volume nodes may not be effective if they simply redistribute volume among lower degree actors, which appears to exacerbate underlying network connectivity.
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    Lifestyles through Expenditures: A Case-Based Approach to Saving.
    (Sociol Sci, 2016) Keister, Lisa A; Benton, Richard; Moody, James
    Treating people as cases that are proximate in a behavior space-representing lifestyles-rather than as markers of single variables has a long history in sociology. Yet, because it is difficult to find analytically tractable ways to implement this idea, this approach is rarely used. We take seriously the idea that people are whole packages, and we use household spending to identify groups who occupy similar positions in social space. Using detailed data on household consumption, we identify eight positions that are clearly similar in lifestyle. We then study how the lifestyles we identify are associated with saving, an important measure of household well-being. We find that households cluster into distinct lifestyles based on similarities and differences in consumption. These lifestyles are meaningfully related in social space and save in distinct ways that have important implications for understanding inequality and stratification.
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    Mapping the semantic structure of cognitive neuroscience.
    (J Cogn Neurosci, 2014-09) Beam, Elizabeth; Appelbaum, L Gregory; Jack, Jordynn; Moody, James; Huettel, Scott A
    Cognitive neuroscience, as a discipline, links the biological systems studied by neuroscience to the processing constructs studied by psychology. By mapping these relations throughout the literature of cognitive neuroscience, we visualize the semantic structure of the discipline and point to directions for future research that will advance its integrative goal. For this purpose, network text analyses were applied to an exhaustive corpus of abstracts collected from five major journals over a 30-month period, including every study that used fMRI to investigate psychological processes. From this, we generate network maps that illustrate the relationships among psychological and anatomical terms, along with centrality statistics that guide inferences about network structure. Three terms--prefrontal cortex, amygdala, and anterior cingulate cortex--dominate the network structure with their high frequency in the literature and the density of their connections with other neuroanatomical terms. From network statistics, we identify terms that are understudied compared with their importance in the network (e.g., insula and thalamus), are underspecified in the language of the discipline (e.g., terms associated with executive function), or are imperfectly integrated with other concepts (e.g., subdisciplines like decision neuroscience that are disconnected from the main network). Taking these results as the basis for prescriptive recommendations, we conclude that semantic analyses provide useful guidance for cognitive neuroscience as a discipline, both by illustrating systematic biases in the conduct and presentation of research and by identifying directions that may be most productive for future research.
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    Predictions of primate-parasite coextinction.
    (Philosophical transactions of the Royal Society of London. Series B, Biological sciences, 2021-11) Herrera, James P; Moody, James; Nunn, Charles L
    Future biodiversity loss threatens the integrity of complex ecological associations, including among hosts and parasites. Almost half of primate species are threatened with extinction, and the loss of threatened hosts could negatively impact parasite associations and ecosystem functions. If endangered hosts are highly connected in host-parasite networks, then future host extinctions will also drive parasite extinctions, destabilizing ecological networks. If threatened hosts are not highly connected, however, then network structure should not be greatly affected by the loss of threatened hosts. Networks with high connectance, modularity, nestedness and robustness are more resilient to perturbations such as the loss of interactions than sparse, nonmodular and non-nested networks. We analysed the interaction network involving 213 primates and 763 parasites and removed threatened primates (114 species) to simulate the effects of extinction. Our analyses revealed that connections to 23% of primate parasites (176 species) may be lost if threatened primates go extinct. In addition, measures of network structure were affected, but in varying ways because threatened hosts have fewer parasite interactions than non-threatened hosts. These results reveal that host extinctions will perturb the host-parasite network and potentially lead to secondary extinctions of parasites. The ecological consequences of these extinctions remain unclear. This article is part of the theme issue 'Infectious disease macroecology: parasite diversity and dynamics across the globe'.
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    Reconsidering Adolescent Society: Racial Differences in Stress Processing, Violence, and Health
    (2024) Coles IV, Bernard Albert

    This dissertation investigates racial differences in individual stress processes and health as well as the ways social networks characteristics mediate these relationships. I explore (1) the stress trajectories of victims and non-victims from adolescence to adulthood across racial groups, (2) how particular network configurations determine the probability of adolescents experiencing victimization, and finally, (3) the ways racial homophily and social cohesion together, determine depressive symptoms. I conduct three studies all using relevant demographic, mental, and physical health data from the National Longitudinal Study of Adolescent to Adult Health. In my first study I find that black respondents have a unique relationship with the stress incurred from victimization, such that black victims and non-victims have virtually equal allostatic loads. In my second study I find that delinquency and integration shape the probability of victimization for adolescents, net of several common correlates of delinquency. Finally, results from my third chapter show that racial homophily mediates the well establish relationship between social cohesion and depression. These findings contribute to the sociology of race and ethnicity, network sociology, and to medical sociological inquires concerned with the vulnerable period of adolescence. Together, these three chapters show that race and networks govern opportunities that individuals have to form positive social relationships and the resulting health consequences of both successful and unsuccessful navigation of one’s social environment.