Learning Aggregation Rules in Participatory Budgeting: A Data-Driven Approach
This work addresses a practical problem for PB organizers by enabling adaptive rule selection, though it is incremental as it builds on existing aggregation methods with a novel application of machine learning.
The paper tackles the challenge of selecting aggregation rules in Participatory Budgeting by proposing a data-driven machine learning approach that learns rules balancing social welfare and representation, demonstrating effectiveness through experiments on synthetic and real-world data.
Participatory Budgeting (PB) offers a democratic process for communities to allocate public funds across various projects through voting. In practice, PB organizers face challenges in selecting aggregation rules either because they are not familiar with the literature and the exact details of every existing rule or because no existing rule echoes their expectations. This paper presents a novel data-driven approach utilizing machine learning to address this challenge. By training neural networks on PB instances, our approach learns aggregation rules that balance social welfare, representation, and other societal beneficial goals. It is able to generalize from small-scale synthetic PB examples to large, real-world PB instances. It is able to learn existing aggregation rules but also generate new rules that adapt to diverse objectives, providing a more nuanced, compromise-driven solution for PB processes. The effectiveness of our approach is demonstrated through extensive experiments with synthetic and real-world PB data, and can expand the use and deployment of PB solutions.