Quadratic voting

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Quadratic voting (sometimes abbreviated QV) is a collective decision-making procedure where participants express how strongly they feel about an issue rather than just whether they are in favor of it or opposed to it.[1][2][3] It addresses issues of voting paradox and majority-rule. According to its creators, Steven P. Lalley[4] and E. Glen Weyl[5], Quadratic voting achieves the greatest possible good for the greatest number of group members, although other proponents of Quadratic voting state that this is only true approximately.[6]


Quadratic voting is based on market principles. Each voter is endowed with a budget of “vote credits” that they may spend to influence the outcome of a range of decisions. If a participant has a strong preference for or against a particular decision, additional votes can be allocated. A vote pricing rule determines the cost of additional votes, with each vote becoming increasingly more expensive.

The quadratic nature of the voting means that a voter can use their votes more efficiently by spreading them across many issues. For example, a voter with a budget of 16 vote credits can apply 1 vote credit to each of 16 issues. However, if they feel strongly about a single issue, they might apply 4 votes, at the cost of 16 credits, to a single issue, using their entire budget.

The quadratic nature of voting means that is a large incentive to buy and sell votes, or to trade votes. But using a totally secret ballot gives some protection against vote buying or trading because such exchanges cannot be verified by the buyer or trader.

Vote Pricing Example
Number of votes “Vote Credit” cost
1 1
2 4
3 9
4 16
5 25


Quadratic Voting was used in an experiment by the Democratic caucus of the Colorado House of Representatives in the Spring of 2019. Lawmakers used it to decide on their legislative priorities for the coming two years, selecting among 107 possible bills.[7]

See also[edit]


  1. ^ Lalley, Steven; Weyl, E. Glen (2017-12-24). "Quadratic Voting: How Mechanism Design Can Radicalize Democracy". Rochester, NY. doi:10.2139/ssrn.2003531.
  2. ^ Lee, Sherman (May 30, 2018). "Quadratic Voting: A New Way to Govern Blockchains for Enterprises". Forbes. Retrieved Mar 13, 2019.
  3. ^ Volpicelli, Gian (14 June 2018). "This economist wants to abolish private property using blockchain". Wired. Retrieved 15 March 2019.
  4. ^ "Steven Lalley - Statistics Faculty". galton.uchicago.edu. Retrieved 2019-07-05.
  5. ^ "Glen Weyl". Retrieved 2019-07-05.
  6. ^ Posner, Eric; Weyl, E. Glen (2018). Radical Markets: uprooting capitalism and democracy for a just society. Princeton. ISBN 9780691177502. OCLC 1030268293.
  7. ^ Coy, Peter (May 1, 2019). "A New Way of Voting That Makes Zealotry Expensive". Bloomberg Businessweek. Retrieved July 5, 2019.

Further reading[edit]

  • US Patent 9754272, E Glen Weyl; David Quarfoot & Eric Posner et al., "System and Method for Quadratic, Near-Quadratic, and Convex Voting in Various Types of Research and Voting", issued 5 September 2017