Approval-Based Participatory Budgeting with Donations

Participatory budgeting (PB) is a democratic process that allows voters to directly participate in the decision-making process regarding budget spending. The process typically involves presenting voters with a range of proposed projects, and the goal is to select a subset of projects that will be funded. We explore the inclusion of donations in approval-based PB. By allowing voters to pledge donations to projects, the total available budget can increase, however, the concern arises that wealthier donors may wield disproportionate influence. Addressing this, we consider three broad classes of aggregation rules and examine whether they satisfy crucial desideratum in PB with donations.