Spread of (mis)information in social networks

• Published in: Games and economic behavior Vol. 70; no. 2; pp. 194 - 227
• Main Authors: Acemoglu, Daron, Ozdaglar, Asuman, ParandehGheibi, Ali
• Format: Journal Article
• Language: English
• Published: Duluth Elsevier Inc 01.11.2010; Elsevier; Academic Press
• Series: Games and Economic Behavior
• Subjects: Agency theory; Belief & doubt; Economic models; False information; Information aggregation; Information aggregation Learning Misinformation Social networks; Information dissemination; Information economics; Information exchange; Information sharing; Learning; Misinformation; Network analysis; Social networks; Studies; Information aggregation; Learning; Social networks; Misinformation; D83; C72
• ISSN: 0899-8256; 1090-2473
• DOI: 10.1016/j.geb.2010.01.005

We provide a model to investigate the tension between information aggregation and spread of misinformation. Individuals meet pairwise and exchange information, which is modeled as both individuals adopting the average of their pre-meeting beliefs. “Forceful” agents influence the beliefs of (some of) the other individuals they meet, but do not change their own opinions. We characterize how the presence of forceful agents interferes with information aggregation. Under the assumption that even forceful agents obtain some information from others, we first show that all beliefs converge to a stochastic consensus. Our main results quantify the extent of misinformation by providing bounds or exact results on the gap between the consensus value and the benchmark without forceful agents (where there is efficient information aggregation). The worst outcomes obtain when there are several forceful agents who update their beliefs only on the basis of information from individuals that have been influenced by them.