The relationship between perceived friendship and proximity networks among Tanzanian Hadza

Abstract

In humans, measures of social integration are usually based on self-reported friendships and interview-derived data. However, such measures do not take into account the actual number of social contacts an individual has, a variable that has been shown to have significant impacts on an individual’s health and well-being. In recent years advances in ‘bio-logging’ – an automated system that registers an individual’s (physical) position relative to others – have made it easier to quantify actual physical proximity between individuals. Here, we use reported friendships and GPS-derived proximity data obtained from 81 adult Hadza men and women living in northern Tanzania to directly compare perceived friendship networks with social networks based on physical proximity. Overall, the results of this study show that even though the pattern of social relationships is similar in both networks (ie individuals tend to have stronger proximity ties with nominated best friends and vice versa), individual measures of social integration, such as the number of social partners and network centrality, do not correspond to each other in the two types of social networks. For example, being central in self-reported friendship networks does not correspond with being central in proximity networks. We discuss these findings in light of study limitations, including a small sample size and challenges regarding comparing networks of different structure.