Beyond the Wisdom of the Crowd: How Network Topology Distorts Collective Perception

TL;DR

This paper demonstrates that social network topology can significantly distort collective perception, leading to biases that persist even after information aggregation, with implications for social cohesion and polarization.

Contribution

It introduces a simple model showing how network structure alone causes perceptual biases and derives an estimator to predict these biases from network features.

Findings

Network topology causes systematic perceptual biases.

Biases persist after data aggregation.

Network structure influences social segregation and polarization.

Abstract

Cognitive biases are often attributed to heuristics or limited information. Yet the structure of social networks is a key, often-overlooked source of perceptual bias. When information passes through social connections, the network alone can systematically distort how individuals view society. We use a simple model in which agents have a binary attribute (e.g., atheist or believer) and show that network topology alone can cause misperceptions of peers' attributes. These misperceptions persist even after aggregation and challenge the idea of the "wisdom of the crowd." We derive an estimator that predicts the size and direction of these biases from network features. We validate our findings using three large-scale opinion surveys. Our results show that network structure is a critical factor in collective perception, with major implications for reducing segregation, polarisation, and the marginalisation of minorities.