The Lacuna Project

lacuna (n.) a gap in a record where something should be

Independent research. Not affiliated with any government, agency, or company.

Exhibit 729

Reranking partisan animosity in algorithmic social media feeds alters affective polarization

Exhibit 729 ยท Peer-reviewed study

Reranking partisan animosity in algorithmic social media feeds alters affective polarization

providing causal evidence that exposure to AAPA content alters affective polarization.

Preregistered 10-day field experiment, 1,256 participants on X during the 2024 campaign, with an independent browser-side reranking method.

Source
Piccardi, Saveski, Jia, Hancock et al. (Science)
Date
27 November 2025
Quoted from
Abstract
Grade
Peer-reviewed
Document
https://doi.org/10.1126/science.adu5584
Accessed
2026-11-09
Cited by
Findings citing this exhibit

Cited by

Finding POL-3.9
Peer-reviewed A preregistered 10-day field experiment on X in 2024 with 1,256 participants, using a browser-side reranking method independent of the platform, found that reranking posts with partisan animosity shifted out-party feelings by more than 2 points on a 100-point scale.
Finding POL-3.11
Open question Whether engagement-optimizing ranking causes lasting polarization, as distinct from what it amplifies and what users see, is unresolved in the peer-reviewed record.