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arXiv · 2512.17243

Who Connects Global Aid? The Hidden Geometry of 10 Million Transactions

Paul X. McCarthy·Xian Gong·Marian-Andrei Rizoiu·Paolo Boldi
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Abstract

The global aid system functions as a complex and evolving ecosystem; yet widespread understanding of its structure remains largely limited to aggregate volume flows. Here we map the network topology of global aid using a dataset of unprecedented scale: over 10 million transaction records connecting 2,456 publishing organisations across 230 countries between 1967 and 2025. We apply bipartite projection and dimensionality reduction to reveal the geometry of the system and unveil hidden patterns. This exposes distinct functional clusters that are otherwise sparsely connected. We find that while governments and multilateral agencies provide the primary resources, a small set of knowledge brokers provide the critical connectivity. Universities and research foundations specifically act as essential bridges between disparate islands of implementers and funders. We identify a core solar system of 25 central actors who drive this connectivity including unanticipated brokers like J-PAL and the Hewlett Foundation. These findings demonstrate that influence in the aid ecosystem flows through structural connectivity as much as financial volume. Our results provide a new framework for donors to identify strategic partners that accelerate coordination and evidence diffusion across the global network.

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Paul X. McCarthy, Xian Gong, Marian-Andrei Rizoiu, Paolo Boldi. 2025-12-19. Who Connects Global Aid? The Hidden Geometry of 10 Million Transactions. https://arxiv.org/abs/2512.17243

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