A Unified Framework for Uniform-Price Resource Allocation Mechanisms

Mechanisms for allocating a divisible resource among strategic agents have been widely studied. The prominent paradigm is the proportional (Kelly) mechanism, which elicits a scalar bid per agent, allocates the resource proportionally, and charges payments equal to the bids. Follow-up mechanisms improve social welfare, but sacrifice simplicity by introducing complex allocation rules or unintuitive payments. We introduce a unified framework for designing simple resource allocation mechanisms with proportional-style allocations and uniform pricing. Our framework yields a family of mechanisms that interpolate between the Kelly mechanism and the first-price auction. These mechanisms strictly improve upon Kelly’s efficiency guarantees, even achieving full efficiency in equilibrium, while also providing revenue guarantees relative to the VCG mechanism. In settings with budget-constrained agents, our mechanisms achieve nearly optimal price of anarchy with respect to the liquid welfare. When budgets are public, our framework further enables the design of mechanisms that ensure budget feasibility, even when agents do not explicitly account for their constraints in their strategies.