Thwarting Vote Buying Through Decoy Ballots

Thwarting Vote Buying Through Decoy Ballots

David C. Parkes, Paul Tylkin, Lirong Xia

Proceedings of the Twenty-Sixth International Joint Conference on Artificial Intelligence
Main track. Pages 3784-3790. https://doi.org/10.24963/ijcai.2017/529

There is increasing interest in promoting participatory democracy, in particular by allowing voting by mail or internet and through random-sample elections. A pernicious concern, though, is that of vote buying, which occurs when a bad actor seeks to buy ballots, paying someone to vote against their own intent. This becomes possible whenever a voter is able to sell evidence of which way she voted. We show how to thwart vote buying through decoy ballots, which are not counted but are indistinguishable from real ballots to a buyer. We show that an Election Authority can significantly reduce the power of vote buying through a small number of optimally distributed decoys, and model societal processes by which decoys could be distributed.
Keywords:
Multidisciplinary Topics and Applications: AI and Social Sciences
Agent-based and Multi-agent Systems: Economic paradigms, auctions and market-based systems
Agent-based and Multi-agent Systems: Social Choice Theory