Why is parochialism prevalent?: an evolutionary approach

Nathan Berg, Jeong-Yoo Kim and Kyu Min Lee
Additional contact information
Kyu Min Lee: KAIST

Journal of Economic Interaction and Coordination, 2021, vol. 16, issue 4, No 3, 769-796

Abstract: Abstract Parochialism occurs when an individual mentally codes the population into in-group and out-group members and cooperates only with in-group members. Conditional cooperation of this kind is distinct from strategies such as tit-for-tat where the decision to cooperate is conditioned on others’ previous actions. Parochialists practice in-group favoritism by cooperating with others, conditional on their spatial proximity or cultural similarity. We consider an evolutionary model of local interaction with three types of strategies: altruists “always cooperate”; egoists “always defect”; and parochialists cooperate only with neighbors within a certain radius on a spatial network. In the model, we provide a new explanation for why parochialism is durable and can stably remain prevalent in human populations. The main driving force is the homophily effect. Interestingly, the homophily effect leads to the prevalence of parochialists but not altruists who benefit more from homophilic association, because altruists are invaded by parochialists. The two groups can coexist only if egoists buffer their direct interaction. Accordingly, the proportion of egoists can be greater than that of altruists in our model, contrary to the result of Eshel et al. (1998). Simulations show, for most parameter values, that the socially optimal cooperation radius (achieving the greatest mean fitness across the entire population) is two and that narrow in-group parochialism is prevalent regardless of frequency of interaction within a society.

Keywords: Altruism; Parochialism; Egoist; Conditional cooperation; Local interaction; Homophily; C73; D64 (search for similar items in EconPapers)
Date: 2021
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (3)

Downloads: (external link)
http://link.springer.com/10.1007/s11403-021-00328-3 Abstract (text/html)
Access to the full text of the articles in this series is restricted.

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:spr:jeicoo:v:16:y:2021:i:4:d:10.1007_s11403-021-00328-3

Ordering information: This journal article can be ordered from
http://www.springer. ... ry/journal/11403/PS2

DOI: 10.1007/s11403-021-00328-3

Access Statistics for this article

Journal of Economic Interaction and Coordination is currently edited by A. Namatame, Thomas Lux and Shu-Heng Chen

More articles in Journal of Economic Interaction and Coordination from Springer, Society for Economic Science with Heterogeneous Interacting Agents Contact information at EDIRC.
Bibliographic data for series maintained by Sonal Shukla () and Springer Nature Abstracting and Indexing ().