Why are U.S. parties so polarized? A "satisficing" dynamical model

Vicky Chuqiao Yang, Daniel M. Abrams, Georgia Kernell, Adilson E. Motter

Research output: Contribution to journalArticlepeer-review

13 Scopus citations

Abstract

Since the 1960s, Democrats and Republicans in the U.S. Congress have taken increas-ingly polarized positions, while the public's policy positions have remained centrist and moderate. We explain this apparent contradiction by developing a dynamical model that predicts ideological positions of political parties. Our approach tackles the challenge of incorporating bounded rationality into mathematical models and integrates the empirical finding of satisficing decision making|voters settle for candidates who are \good enough" when deciding for whom to vote. We test the model using data from the U.S. Congress over the past 150 years and find that our predictions are consistent with the two major political parties' historical trajectories. In particular, the model explains how polariza-tion between the Democrats and Republicans since the 1960s could be a consequence of increasing ideological homogeneity within the parties.

Original languageEnglish (US)
Pages (from-to)646-657
Number of pages12
JournalSIAM Review
Volume62
Issue number3
DOIs
StatePublished - 2020

Funding

∗Received by the editors April 5, 2019; accepted for publication (in revised form) March 10, 2020; published electronically August 6, 2020. https://doi.org/10.1137/19M1254246 Funding: This work was supported by the James S. McDonnell Foundation through grant 220020230, the Northwestern University’s Data Science Initiative, Suzanne Hurst and Samuel Peters, and the Santa Fe Institute Omidyar Fellowship. †Santa Fe Institute, Santa Fe, NM 87501 ([email protected]). ‡Department of Engineering Sciences and Applied Mathematics, and Northwestern Institute on Complex Systems, Northwestern University, Evanston, IL 60208 ([email protected]). §Departments of Communication and Political Science, University of California, Los Angeles, Los Angeles, CA 90095 ([email protected]). ¶Department of Physics and Astronomy, and Northwestern Institute on Complex Systems, North-western University, Evanston, IL 60208 ([email protected]).

Keywords

  • Bounded rationality
  • Dynamical systems
  • Satiscing
  • Social systems
  • Voting

ASJC Scopus subject areas

  • Theoretical Computer Science
  • Computational Mathematics
  • Applied Mathematics

Fingerprint

Dive into the research topics of 'Why are U.S. parties so polarized? A "satisficing" dynamical model'. Together they form a unique fingerprint.

Cite this