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arXiv · 2509.18343

Fair Decisions through Plurality: Results from a Crowdfunding Platform

Joel Miller·E. Glen Weyl·Chris Kanich
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Abstract

We discuss an algorithmic intervention aimed at increasing equity and economic efficiency at a crowdfunding platform that gives cash subsidies to grantees. Through a blend of technical and qualitative methods, we show that the previous algorithm used by the platform -- Quadratic Funding (QF) -- suffered problems because its design was rooted in a model of individuals as isolated and selfish. We present an alternative algorithm -- Connection-Oriented Quadratic Funding (CO-QF) -- rooted in a theory of plurality and prosocial utilities, and show that it qualitatively and quantitatively performs better than QF. CO-QF has achieved an 89% adoption rate at the platform and has distributed over $4 Million to date. In simulations we show that it provides better social welfare than QF. While our design for CO-QF was responsive to the needs of a specific community, we also extrapolate out of this context to show that CO-QF is a potentially helpful tool for general-purpose public decision making.

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Joel Miller, E. Glen Weyl, Chris Kanich. 2025-09-22. Fair Decisions through Plurality: Results from a Crowdfunding Platform. https://doi.org/10.1145/3757887.3763019

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