@inproceedings{lei-etal-2026-truth,
title = "Truth or Tribe: How In-group Favoritism Prioritize Facts in Persona Agents",
author = "Lei, Shijun and
Wang, Hongyu and
Liang, Yunji and
Zheng, Haowen and
Guo, Bin and
Yu, Zhiwen",
editor = "Lee, Hung-Yi and
Dev, Sunipa and
Li, Jessy and
Elliott, Desmond",
booktitle = "Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing",
month = oct,
year = "2026",
address = "Budapest, Hungary",
publisher = "Association for Computational Linguistics",
url = "https://aclanthology.org/2026.emnlp-main.505/",
pages = "11596--11617",
ISBN = "979-8-89176-459-0",
abstract = "In-group favoritism refers to the phenomenon of favoring members of one{'}s in-group over out-group members and is widely observed in numerous social cooperative behaviors. Recently, in-group favoritism biases have also been identified in generative language models. However, whether persona agents exhibit in-group favoritism when faced with conflicting information, including misinformation, and how to mitigate its adverse effects remain understudied. To address these problems, we propose a Truth or Tribe simulation framework to study agent cooperation in the spread of conflicting information through a triadic interaction paradigm, and conduct controlled trials to evaluate the primary moderating factors. Extensive results showcase that persona agents display strong in-group favoritism, accepting incorrect answers from identity-similar peers at much higher rates than from dissimilar peers. In-group favoritism continues to emerge in defeasible reasoning contexts where no absolute truth exists, and it intensifies as cognitive complexity increases. Furthermore, three intervention strategies{---}Identity-Blind Instruction, Structured Counterfactual Reasoning, and Heterogeneous Perspective Ensemble{---}are proposed to mitigate in-group favoritism."
}<?xml version="1.0" encoding="UTF-8"?>
<modsCollection xmlns="http://www.loc.gov/mods/v3">
<mods ID="lei-etal-2026-truth">
<titleInfo>
<title>Truth or Tribe: How In-group Favoritism Prioritize Facts in Persona Agents</title>
</titleInfo>
<name type="personal">
<namePart type="given">Shijun</namePart>
<namePart type="family">Lei</namePart>
<role>
<roleTerm authority="marcrelator" type="text">author</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Hongyu</namePart>
<namePart type="family">Wang</namePart>
<role>
<roleTerm authority="marcrelator" type="text">author</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Yunji</namePart>
<namePart type="family">Liang</namePart>
<role>
<roleTerm authority="marcrelator" type="text">author</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Haowen</namePart>
<namePart type="family">Zheng</namePart>
<role>
<roleTerm authority="marcrelator" type="text">author</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Bin</namePart>
<namePart type="family">Guo</namePart>
<role>
<roleTerm authority="marcrelator" type="text">author</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Zhiwen</namePart>
<namePart type="family">Yu</namePart>
<role>
<roleTerm authority="marcrelator" type="text">author</roleTerm>
</role>
</name>
<originInfo>
<dateIssued>2026-10</dateIssued>
</originInfo>
<typeOfResource>text</typeOfResource>
<relatedItem type="host">
<titleInfo>
<title>Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing</title>
</titleInfo>
<name type="personal">
<namePart type="given">Hung-Yi</namePart>
<namePart type="family">Lee</namePart>
<role>
<roleTerm authority="marcrelator" type="text">editor</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Sunipa</namePart>
<namePart type="family">Dev</namePart>
<role>
<roleTerm authority="marcrelator" type="text">editor</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Jessy</namePart>
<namePart type="family">Li</namePart>
<role>
<roleTerm authority="marcrelator" type="text">editor</roleTerm>
</role>
</name>
<name type="personal">
<namePart type="given">Desmond</namePart>
<namePart type="family">Elliott</namePart>
<role>
<roleTerm authority="marcrelator" type="text">editor</roleTerm>
</role>
</name>
<originInfo>
<publisher>Association for Computational Linguistics</publisher>
<place>
<placeTerm type="text">Budapest, Hungary</placeTerm>
</place>
</originInfo>
<genre authority="marcgt">conference publication</genre>
<identifier type="isbn">979-8-89176-459-0</identifier>
</relatedItem>
<abstract>In-group favoritism refers to the phenomenon of favoring members of one’s in-group over out-group members and is widely observed in numerous social cooperative behaviors. Recently, in-group favoritism biases have also been identified in generative language models. However, whether persona agents exhibit in-group favoritism when faced with conflicting information, including misinformation, and how to mitigate its adverse effects remain understudied. To address these problems, we propose a Truth or Tribe simulation framework to study agent cooperation in the spread of conflicting information through a triadic interaction paradigm, and conduct controlled trials to evaluate the primary moderating factors. Extensive results showcase that persona agents display strong in-group favoritism, accepting incorrect answers from identity-similar peers at much higher rates than from dissimilar peers. In-group favoritism continues to emerge in defeasible reasoning contexts where no absolute truth exists, and it intensifies as cognitive complexity increases. Furthermore, three intervention strategies—Identity-Blind Instruction, Structured Counterfactual Reasoning, and Heterogeneous Perspective Ensemble—are proposed to mitigate in-group favoritism.</abstract>
<identifier type="citekey">lei-etal-2026-truth</identifier>
<location>
<url>https://aclanthology.org/2026.emnlp-main.505/</url>
</location>
<part>
<date>2026-10</date>
<extent unit="page">
<start>11596</start>
<end>11617</end>
</extent>
</part>
</mods>
</modsCollection>
%0 Conference Proceedings
%T Truth or Tribe: How In-group Favoritism Prioritize Facts in Persona Agents
%A Lei, Shijun
%A Wang, Hongyu
%A Liang, Yunji
%A Zheng, Haowen
%A Guo, Bin
%A Yu, Zhiwen
%Y Lee, Hung-Yi
%Y Dev, Sunipa
%Y Li, Jessy
%Y Elliott, Desmond
%S Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
%D 2026
%8 October
%I Association for Computational Linguistics
%C Budapest, Hungary
%@ 979-8-89176-459-0
%F lei-etal-2026-truth
%X In-group favoritism refers to the phenomenon of favoring members of one’s in-group over out-group members and is widely observed in numerous social cooperative behaviors. Recently, in-group favoritism biases have also been identified in generative language models. However, whether persona agents exhibit in-group favoritism when faced with conflicting information, including misinformation, and how to mitigate its adverse effects remain understudied. To address these problems, we propose a Truth or Tribe simulation framework to study agent cooperation in the spread of conflicting information through a triadic interaction paradigm, and conduct controlled trials to evaluate the primary moderating factors. Extensive results showcase that persona agents display strong in-group favoritism, accepting incorrect answers from identity-similar peers at much higher rates than from dissimilar peers. In-group favoritism continues to emerge in defeasible reasoning contexts where no absolute truth exists, and it intensifies as cognitive complexity increases. Furthermore, three intervention strategies—Identity-Blind Instruction, Structured Counterfactual Reasoning, and Heterogeneous Perspective Ensemble—are proposed to mitigate in-group favoritism.
%U https://aclanthology.org/2026.emnlp-main.505/
%P 11596-11617
Markdown (Informal)
[Truth or Tribe: How In-group Favoritism Prioritize Facts in Persona Agents](https://aclanthology.org/2026.emnlp-main.505/) (Lei et al., EMNLP 2026)
ACL