Liquid Democracy: An Algorithmic Perspective
We study liquid democracy, a collective decision making paradigm that allows voters to transitively delegate their votes, through an algorithmic lens. In our model, there are two alternatives, one correct and one incorrect, and we are interested in the probability that the majority opinion is correct. Our main question is whether there exist delegation mechanisms that are guaranteed to outperform direct voting, in the sense of being always at least as likely, and sometimes more likely, to make a correct decision. Even though we assume that voters can only delegate their votes to better-informed voters, we show that local delegation mechanisms, which only take the local neighborhood of each voter as input (and, arguably, capture the spirit of liquid democracy), cannot provide the foregoing guarantee. By contrast, we design a non-local delegation mechanism that does provably outperform direct voting under mild assumptions about voters.
Authors:
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Award ID(s):
Publication Date:
NSF-PAR ID:
10250703
Journal Name:
Journal of Artificial Intelligence Research
Volume:
70
Page Range or eLocation-ID:
1223 to 1252
ISSN:
1076-9757
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