The Social Network: How People Infer Relationships From Mutual Connections.

People infer that individuals are socially related if they have overlapping preferences, beliefs, and choices. Here we examined whether people also infer relationships by attending to social network information. In five preregistered experiments, participants were shown the social networks of two target people and their friends or acquaintances within a group, and judged if the targets were socially related to one another. In the first three experiments, adults (total N = 528) were more likely to judge that individuals were friends when a high rather than low proportion of their friendships were mutual. Adults also considered other factors when inferring friendships, such as the number of friends each individual had. In the final two experiments, 5-7-year-olds (total N = 135) were also sensitive to the proportion of mutual relationships. Together, our work suggests that people use proportional information and statistical inferences when assessing whether individuals are socially related. [ABSTRACT FROM AUTHOR]