Social network size in humans

By R. A. Hill, Robin I. M. Dunbar. Human Nature, 2003

1,031 citations recorded by the source corpus.

This paper examines social network size in contemporary Western society based on the exchange of Christmas cards. Maximum network size averaged 153.5 individuals, with a mean network size of 124.9 for those individuals explicitly contacted; these values are remarkably close to the group size of 150 predicted for humans on the basis of the size of their neocortex. Age, household type, and the relationship to the individual influence network structure, although the proportion of kin remained relatively constant at around 21%. Frequency of contact between network members was primarily determined by two classes of variable: passive factors (distance, work colleague, overseas) and active factors (emotional closeness, genetic relatedness). Controlling for the influence of passive factors on contact rates allowed the hierarchical structure of human social groups to be delimited. These findings suggest that there may be cognitive constraints on network size.

Subfields: Experimental and Cognitive Psychology, Social Psychology, Sociology and Political Science

View Paper: https://www.semanticscholar.org/paper/ded7d96549cf3ed0d479eafd716c8fd2bb1301de

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Citations in the corpus

The Social Brain: Mind, Language, and Society in Evolutionary Perspective (2003, methodology): “…regression equation for pri mates was used to predict social group size in modern humans, it yielded a value of about 150 that turned out to be a remarkably common value at one particular level in the hierarchy of social organization in a wide range of societies (Dunbar 1992b, Hill & Dunbar 2003).”
Growing closer on facebook: changes in tie strength through social network site use (2014, background): “As a result, maintaining a portfolio of relationships requires sizable investment [18].”
The “online brain”: how the Internet may be changing our cognition (2019, background): “…more time on social media and smartphones have a greater prevalence of mental health problems, including depression, than those who spent more time on “nonscreen” activities 116 , with greater than 5 hrs/day (versus 1 hr/day) associated with 66% increased risk of one suiciderelated outcome 117 .”
Providing Adaptive Health Updates Across the Personal Social Network (2014, methodology): “Major life events such as going to university, marriage, childbearing (Hill & Dunbar, 2003), and divorce (Milardo, 1987) can cause fluctuations in network membership and size.”
Do online social media cut through the constraints that limit the size of offline social networks? (2016, background): “On the basis of a projection from an equation relating social community size to neocortex volume in apes, it had previously been suggested that there is a natural group size for humans [18], and this has been validated against hunter–gatherer community sizes [19,20] as well as the sizes of offline p”
A visual analytics approach to understanding cycling behaviour (2012, neutral): “It is observed that the deformation increases with the distance similar to case 2, while there is also a very good agreement between the simulation and the experiment.”
Mind the gap; or why humans are not just great apes (2008, background): “Rather, it seems that our social world consists of a series of hierarchically inclusive circles of acquaintanceship that are reflected in both the perceived intimacy of the relationship and the frequency of interaction (Hill and Dunbar 2003).”
Ventromedial prefrontal volume predicts understanding of others and social network size (2011, background): “Personal social networks consist of a series of concentric layers that include progressively more individuals, with the size of the layers scaling with each other with a constant scaling ratio of about 3 (Hill & Dunbar 2003; Zhou et al. 2005; Hamilton et al. 2007).”
Collective aspects of privacy in the Twitter social network (2018, background): “While social network arguments support this assumption [26, 33], future research should aim at accessing friendship lists or name generators that do not depend on online interaction.”
The Neurobiology of Social Distance (2020, positive): “This gives rise to a very distinctive layering to our social networks in which the layers have a characteristic fractal pattern: the innermost layers of closest friends is very small (typically five people) but intense, the outermost (~150) very large but more casual [67,68].”
The long tail of social networking.: Revenue models of social networking sites (2008, background): “Sociological studies concluded that the average size of people’s immediate social contacts is 124 people (Hill and Dunbar, 2003).”
Synchrony as an Adaptive Mechanism for Large-Scale Human Social Bonding (2016, positive): “…Dunbar 1992) is applicable to a wide variety of interpersonal situations, including hunter-gatherer clans (Dunbar 1993), Christmas card networks (Hill & Dunbar 2003), and active Facebook relationships (Arnaboldi et al. 2013; Dunbar et al. 2015; Dunbar 2016), yet we can also experience a sense…”
Chimps of a feather sit together: chimpanzee friendships are based on homophily in personality (2014, background): “…including kin vs. non-kin (Chapais, 2001; Silk, 2002), and, generally, 154 ‘friends’ vs. ‘non-friends’ (Massen et al., 2010; Fraser et al. 2008), and are also 155 known to be reliable predictors of human friendships (Hinde, 1981) even in 156 contemporary Western societies (Hill & Dunbar, 2003).”