A person’s social network constitutes a rich sampling space for informing judgments about social statistics (e.g., the distribution of preferences, risks, or behaviors in the broader social environment). How is this sampling space searched and used to make inferences? This chapter gives an overview on research on the social-circle model, a computational process account of how people make inferences about relative event frequencies. The social-circle model is inspired by the notion of sequential and limited search in models of bounded rationality for multi-attribute decision making. In accord with research on the structure of social memory, the model assumes that social sampling proceeds by sequentially probing a person’s social circles – including oneself, family, friends, and acquaintances – and that search is constrained by a simple stopping rule. The social-circle model has several free parameters that enable it to capture individual differences in the order in which social circles are inspected, in noise during evidence evaluation, and in discrimination thresholds. We provide a step-by-step tutorial for deriving predictions of the social-circle model, review empirical tests of the model, illustrate how the model reflects individual differences in social sampling and differences in sampling across domains, and analyze the ecological rationality of heuristic social sampling.

People have the ability to estimate frequencies of different behaviors, beliefs, and intentions of others, allowing them to fit into their immediate social worlds, learn from, and cooperate with others. However, psychology has produced a long list of apparent biases in social cognition. We show that this apparent contradiction can be resolved by understanding how cognitive processes underlying social judgments interact with the properties of social and task environments. We describe our social sampling model that incorporates this interaction and can explain biases in people’s estimates of broader populations. We also show that asking people about their social circles produces better predictions of elections than asking about their own voting intentions, provides good description of population attributes, and helps predict people’s future voting and vaccination behavior.

The concept of a “focus of activity” was developed to describe the nature of non-network social structures that often underly the formation of intersecting clusters of ties in large-scale social networks. The primary purpose of the “focus theory” was to encourage network analysts to consider the impact of those underlying structures before attributing too much of the structure and consequences of social networks to psychological processes, individual choices, or self-contained network processes. We have been pleased to see that network researchers have increasingly considered the impacts of these non-network social structures. Nevertheless, we take this opportunity to clarify and extend the focus theory in ways that may make it more applicable and useful for more purposes. We show how the focus theory can be reconciled with some influential network theories that may initially appear inconsistent with it. We discuss how the focused organization facilitates indirect connections across large-scale social networks; and, we explicitly extend the focus theory by considering additional processes causing both the loss of old ties and the accumulation of new ties within clusters over time.

The authors begin by describing the theoretical framework on which they have based their analysis of the processes they present in this and subsequent chapters. It seeks to account for the interactions between circles, relationships, and networks and to keep in mind that one does not exist without the others. Three main types of contexts for the emergence of relationships are then successively explored: their construction within a social circle; interactions around shared issues; and the extension of the network by the introduction of people through shared relationships. Once constructed, relationships acquire a certain autonomy regarding their context of emergence, which can be captured by the way respondents designate them. Finally, this chapter ends with a review of how social differences (age, gender, level of education, occupation) are perceived (and partly elaborated) in the processes of relationship construction.