This chapter seeks to resolve the puzzle of people’s low accuracy in perceptions of local network properties versus their much higher accuracy in perceiving global network structures. We argue that this puzzle is more apparent than real because humans rely on layers of relational schemata—mental structures dictating how social agents ought to be structurally connected—to mentally organize their social contacts. In other words, differences in accuracy reflect differences in the schemata used by the individual to mentally represent social network information at varying levels (e.g., dyadic level, triadic level, and community level). Individuals vary in their schemata repertoire, and their tendencies to adopt certain schemata in a given situation or context, so the specific set of schemata that individuals activate varies in its sufficiency and appropriateness for fully representing the network structure. We define these individual differences as network representation capacities, and review and compare four prominent approaches to quantifying them: the error paradigm, the free-recall paradigm, the structural learning paradigm and the statistical learning paradigm. We conclude by inviting researchers to reconsider the relations between cognition and egocentric networks, as well as the role of network analysis in analyzing, describing and prescribing social relational behavior.

This chapter reviews all of the articles on informant accuracy produced by Bernard, Killworth and their colleagues, as well as the rebuttal articles that followed from various authors. Several important technological and methodological advancements came from this line of research that have had an enormous impact social network analysis and other disciplines. The second half of the chapter examines the implications of this research on personal network data collection and analysis and the reliability of results from those studies. A key question addressed in this chapter is whether the compositional and structural properties of personal networks, as reported by ego, are reliable given what we know about informant accuracy. I consider whether personal networks represent the real social context surrounding ego, or only their perception of that context, and how this affects the outcome variables that can be predicted with personal network data.