# Civic Crowdfunding for Agents with Negative Valuations and Agents with Asymmetric Beliefs

## TL;DR

This paper introduces novel civic crowdfunding mechanisms that accommodate agents with negative valuations and asymmetric beliefs, enhancing the inclusivity and strategic incentives of public project funding.

## Contribution

It develops new mechanisms, PPRN and PPSN, for negative valuations, and PPRx and PPSx, for asymmetric beliefs, extending existing models to more realistic scenarios.

## Key findings

- Agents with higher belief contribute more in PPRx and PPSx.
- Proposed mechanisms incentivize truthful contribution based on true preferences.
- The mechanisms ensure project provision at equilibrium.

## Abstract

In the last decade, civic crowdfunding has proved to be effective in generating funds for the provision of public projects. However, the existing literature deals only with citizen's with positive valuation and symmetric belief towards the project's provision. In this work, we present novel mechanisms which break these two barriers, i.e., mechanisms which incorporate negative valuation and asymmetric belief, independently. For negative valuation, we present a methodology for converting existing mechanisms to mechanisms that incorporate agents with negative valuations. Particularly, we adapt existing PPR and PPS mechanisms, to present novel PPRN and PPSN mechanisms which incentivize strategic agents to contribute to the project based on their true preference. With respect to asymmetric belief, we propose a reward scheme Belief Based Reward (BBR) based on Robust Bayesian Truth Serum mechanism. With BBR, we propose a general mechanism for civic crowdfunding which incorporates asymmetric agents. We leverage PPR and PPS, to present PPRx and PPSx. We prove that in PPRx and PPSx, agents with greater belief towards the project's provision contribute more than agents with lesser belief. Further, we also show that contributions are such that the project is provisioned at equilibrium.