Cooperative behavior constitutes a key aspect of human society and non-human animal systems, but explaining how cooperation evolves represents a major scientific challenge. It is now well established that social network structure plays a central role for the viability of cooperation. However, not much is known about the importance of the positions of cooperators in the networks for the evolution of cooperation. Here, we investigate how the spread of cooperation is affected by correlations between cooperativeness and individual social connectedness (such that cooperators occupy well-connected network positions). Using simulation models, we find that these correlations enhance cooperation in standard scale-free networks but not in standard Poisson networks. In contrast, when degree assortativity is increased such that individuals cluster with others of similar social connectedness, we find that Poisson networks can maintain high levels of cooperation, which can even exceed those of scale-free networks. We show that this is due to dynamics where bridge areas between social clusters act as barriers to the spread of defection. We also find that this positive effect on cooperation is sensitive to the presence of Trojan horses (defectors placed within cooperator clusters), which allow defection to invade. The results provide new knowledge about the conditions under which cooperation may evolve, and are also relevant to consider in regard to the design of cooperation studies.

Debate regarding the continuity of Cypriot political forms from the Late Bronze Age to the Cypro-Archaic is persistent, resulting in a scholarly divide with few signs of resolution. This article reviews the historiography of political forms proposed for Cyprus as the essential context for this debate. It considers several major themes that emerge from the debate: the use of anthropological models for state formation, regionalism, social networks, and the nature of spatial power. The author views the debate as centred on two equally valid motivations: using related social science theory to enhance archaeological explanation and emphasizing Cypriot autonomy. These motivations need not be set in opposition but, together, illustrate the island's unique history and provide the basis for vibrant scholarship.

The moderation of user-generated content on online platforms remains a key solution to protecting people online, but also remains a perpetual challenge as the appropriateness of content moderation guidelines depends on the online community that they aim to govern. This challenge affects marginalized groups in particular, as they more frequently experience online abuse but also end up falsely being the target of content-moderation guidelines. While there have been calls for democratic, community-moderation, there has so far been little research into how to implement such approaches. Here, we present the co-creation of content moderation strategies with the users of an online platform to address some of these challenges. Within the context of AutSPACEs—an online citizen science platform that aims to allow autistic people to share their own sensory processing experiences publicly—we used a community-based and participatory approach to co-design a content moderation solution that would fit the preferences, priorities, and needs of its autistic user community. We outline how this approach helped us discover context-specific moderation dilemmas around participant safety and well-being and how we addressed those. These trade-offs have resulted in a moderation design that differs from more general social networks in aspects such as how to contribute, when to moderate, and what to moderate. While these dilemmas, processes, and solutions are specific to the context of AutSPACEs, we highlight how the co-design approach itself could be applied and useful for other communities to uncover challenges and help other online spaces to embed safety and empowerment.

This article focuses on the involvement of Viennese elites in wide-reaching political conflicts around 1400. Central European princes often held positions as city lords, which resulted in ambivalent relations between them and urban elites, as well as with their kin residing in the countryside. Setting aside grand categories of institutional history in favor of the interactions and relations of concrete actors, their social networks, and their involvement in shaping politics, the article follows six urban actors through a major conflict that involved the city lords, urban authorities, and individual actors and eventually resulted in the beheading of three of them. The article adopts a prosopographical approach to find out more about patterns of social costs and benefits in these conflicts. It argues that considering polyvalent and relational dimensions of belonging can help us better understand constellations of conflict and alliance and the modes and mechanisms of late medieval politics. It eventually establishes the boundaries of social network approaches when it comes to assessing individual motives and their alleged resonance in contemporary narratives of community.

The nine articles in this collection are the product of two workshops hosted at the University of Chicago in 2022 and 2023 in affiliation with the University of Vienna. They build on recent work that has called attention to the extraordinary political and religious diversity in the fifteenth-century Holy Roman Empire, and Central Europe more broadly. Pushing back against older historiography, in which this period was frequently overlooked or framed by uncritical use of such broad categories as the “state,” the “territory,” the “estates,” and the “feud,” this collection recognizes the polycentric nature of the fifteenth century's structures and institutions. Specifically, these articles return to the sources, especially documents of practice rather than normative texts, to open the door to a new understanding of conflicts and negotiations. They illuminate the patterns of conflict and negotiation evident in specific historical contexts by examining actors, networks, and practices of community building—as well as the processes through which conflicts emerged, evolved, and were negotiated and settled. Rather than relying on time-honored categories and meta-narratives, the contributors embrace the messiness of social and political relations and of the extant source material to shine new light on key themes in the fifteenth century's history.

Group-living creates stresses that, all else equal, naturally lead to group fragmentation, and hence loss of the benefits that group-living provides. How species that live in large stable groups counteract these forces is not well understood. I use comparative data on grooming networks and cognitive abilities in primates to show that living in large, stable groups has involved a series of structural solutions designed to create chains of ‘friendship’ (friends-of-friends effects), increased investment in bonding behaviours (made possible by dietary adjustments) to ensure that coalitions work effectively, and neuronally expensive cognitive skills of the kind known to underpin social relationships in humans. The first ensures that individuals synchronise their activity cycles; the second allows the stresses created by group-living to be defused; and the third allows a large number of weak ties to be managed. Between them, these create a form of multilevel sociality based on strong versus weak ties similar to that found in human social networks. In primates, these strategies appear successively at quite specific group sizes, suggesting that they are solutions to ‘glass ceilings’ that would otherwise limit the range of group sizes that animals can live in (and hence the habitats they can occupy). This sequence maps closely onto the grades now known to underpin the Social Brain Hypothesis and the fractal pattern that is known to optimise information flow round networks.

A vast and growing quantitative literature considers how social networks shape political mobilization but the degree to which turnout decisions are strategic remains ambiguous. Unlike previous studies, we establish personal links between voters and candidates and exploit discontinuous incentives to mobilize across district boundaries to estimate causal effects. Considering three types of networks – families, co-workers, and immigrant communities – we show that a group member's candidacy acts as a mobilizational impulse propagating through the group's network. In family networks, some of this impulse is non-strategic, surviving past district boundaries. However, the bulk of family mobilization is bound by the candidate's district boundary, as is the entirety of the mobilizational effects in the other networks.

The number of studies examining gender differences in the social relationship rewards associated with costly religious practice has been surprisingly low. Here, we use data from 289 residents of an agricultural Tibetan village to assess whether individuals are more inclined to establish supportive relationships with religious individuals in general and to investigate the gender disparities in the relationship between religiosity and personal network characteristics. Our results reveal that participation in religious rituals contributes to the overall development of social support networks. The benefits to personal networks, however, seem to be contingent upon gender. For resource-intensive, infrequent religious rituals such as distant pilgrimages, males seem to benefit slightly more in terms of elevated in-degree values in their personal networks, despite similar levels of investment as females. In contrast, for daily, low-cost religious practices requiring ongoing participation, both genders obtain similar increases in in-degree values through regular engagement. It becomes more challenging for women to increase their status in communities when the effort invested in religious rituals yields smaller rewards compared with the same effort by men, contributing to ongoing gender inequality. These findings highlight the importance of examining the particular characteristics of religious rituals and the gender disparities in the associated rewards.

This article studies the association between the characteristics of individuals’ social networks and expectations of career advancement, including pay raises and job promotions. The literature has extensively documented the role of social capital as a determinant of labour market outcomes. However, the formation of expectations constitutes another critical path by which social ties may affect work through their influence on individual motivation and behaviour. This study attempts to explain the relationship between social capital and career-related expectations and empirically assesses these associations by employing data from a survey administered to a representative sample of the Spanish population. Our findings suggest that the ability to mobilise network resources is positively linked with both measures of career advancement. However, access to the upper class is only positively associated with expecting a pay rise. Additionally, for non-employed individuals, higher mobilisation is positively associated with the expectation of an increase in income.

Social network analysis is known to provide a wealth of insights relevant to many aspects of policymaking. Yet, the social data needed to construct social networks are not always available. Furthermore, even when they are, interpreting such networks often relies on extraneous knowledge. Here, we propose an approach to infer social networks directly from the texts produced by actors and the terminological similarities that these texts exhibit. This approach relies on fitting a topic model to the texts produced by these actors and measuring topic profile correlations between actors. This reveals what can be called “hidden communities of interest,” that is, groups of actors sharing similar semantic contents but whose social relationships with one another may be unknown or underlying. Network interpretation follows from the topic model. Diachronic perspectives can also be built by modeling the networks over different time periods and mapping genealogical relationships between communities. As a case study, the approach is deployed over a working corpus of academic articles (domain of philosophy of science; N=16,917).

Social media is not a neutral channel. How visible information posted online is depends on many factors such as the network structure, the emotional volatility of the content, and the design of the social media platform. In this paper, we use formal methods to study the visibility of agents and information in a social network, as well as how vulnerable the network is to exploitation. We introduce a modal logic to reason about a social network of agents that can follow each other, post, and share information. We show that by imposing some simple rules on the system, a potentially malicious agent can take advantage of the network construction to post an unpopular opinion that may reach many agents. The network is presented both in static and dynamic forms. We prove completeness, expressivity, and model checking problem complexity results for the corresponding logical systems.

La costa del Pacífico de los Andes meridionales tiene una larga historia ocupacional que muestra una diversificación regional hacia el Holoceno medio y tardío. La costa del centro norte de Chile tuvo una importante ocupación cazadora-recolectora entre 6000 y 2000 cal aP, que difiere de las observadas en áreas vecinas por sus características ambientales e históricas. Los estudios de contextos funerarios revelan que estos grupos experimentaron una expansión demográfica y vivieron conflictos sociales durante este período. Sin embargo, el énfasis en la importancia de los contextos funerarios entre 6000 y 2000 cal aP ha limitado nuestro conocimiento de las estrategias medioambientales de estos grupos y el uso de los recursos costeros. Esta investigación examina evidencias recuperadas de contextos residenciales y funerarios del sitio Punta Teatinos (Bahía de Coquimbo, costa centro norte de Chile, 29°S) para evaluar las estrategias de uso ambiental aplicadas. El estudio de estas evidencias —incluyendo estratigrafía, fechados radiocarbónicos, material lítico, malacológico y zooarqueológico; microfósiles, cálculos dentales, isótopos estables y arte rupestre— indican una explotación de recursos costeros, a los que se sumaron otros de origen terrestre. Aunque no se identificaron cambios temporales en la explotación de los recursos costeros, las pruebas también indican cambios en la constitución de los paisajes históricos y de las redes sociales extrarregionales.

Bilingualism is an experience that varies across a continuum and can change across the lifespan. Psychometric research is an underexplored avenue with the potential to further our understanding of the mechanisms and traits underlying bilingual experiences. Here, we developed and validated a social network questionnaire to measure sociolinguistic features in 212 individuals via personal social network. Confirmatory factor analysis examined the measurement structure of the variables. Compared to a one-factor model, the best fitting model was a two-factor model in which the language experience of the individual (i.e., ego) and the language experience of the individual's network (i.e., alters) were correlated latent factors under which aspects of the bilingual experience loaded. Additional analyses revealed other potential ways to examine the data in future analyses. These results provide the first measurement model of bilingual experiences, and provide support for theoretical accounts suggesting differential neuropsychological outcomes based on individual bilingual variability. The results also support the use of social network tools to capture differences in bilingualism.