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Homophily and acrophily as drivers of political segregation


Political segregation is an important social problem, increasing polarization and impeding effective governance. Previous work has viewed the central driver of segregation to be political homophily, the tendency to associate with others who have similar views. Here we propose that, in addition to homophily, people’s social tie decisions are driven by political acrophily, the tendency to associate with others who have more extreme political views (rather than more moderate). We examined this using a paradigm in which participants share emotions and attitudes on political policies, observe others’ responses and choose which others to affiliate with. In four studies (N = 1,235), both liberal and conservative participants’ social tie decisions reflected the presence of acrophily. We found that participants who viewed peers who expressed more extreme views as more prototypical of their political group also tended to engage in greater acrophily. These studies identify a previously overlooked tendency in tie formation.

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Fig. 1: Three hypothetical tie selection strategies.
Fig. 2: An outline of a trial in the choice condition.
Fig. 3: Results from study 2 (n = 213, experimental condition).
Fig. 4: Results from study 3.
Fig. 5: Task and results of study 4.

Data availability

Data for study 1 are available here: Data for studies 2–4 are available here: Data for the agent-based model are available here:

Code availability

Code for study 1 is available here: Code for studies 2–4 is available here: Code for the agent-based model is available here:


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The authors thank M. Reyes, N. Ebeid and N. Hunt for their assistance in running the lab studies, V. Puri for her assistance in developing the simulations and processing the peer information, and A. Boutyline and J. Jordan for their comments on the research. J.S. is supported in part by the German Academic Scholarship Foundation (Promotionsförderung der Studienstiftung des deutschen Volkes). The funder had no role in study design, data collection and analysis, decision to publish or preparation of the manuscript.

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A.G., J.J.G., E.H., R.W. and J.M.A. conceived and designed the experiments. A.G., Z.H., J.S. and D.B. ran the experiments. A.G. and J.M.A. analysed studies 1–4. A.G. wrote the paper, and E.H., R.W., J.M.A. and J.J.G. were involved in reviewing and editing the manuscript.

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Correspondence to Amit Goldenberg.

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Goldenberg, A., Abruzzo, J.M., Huang, Z. et al. Homophily and acrophily as drivers of political segregation. Nat Hum Behav (2022).

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