Quadratic voting (sometimes abbreviated QV) is a collective decision-making procedure, where participants cast their preference and intensity of preference for each decision (as opposed to a simple for or against decision).
According to its authors Steven P. Lalley and E. Glen Weyl, Quadratic voting is claimed to achieve the greatest possible good for the greatest number of group members although other proponents of Quadratic Voting admit that is at best an approximation. It addresses issues of voting paradox and majority-rule.
Based on market principles, each voter is endowed with a budget of “voice credits” that they may spend influencing 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, whereby each vote increasingly becomes more expensive.
The quadratic nature of the voting means that a voter can use his or her votes more efficiently spread across many issues. For example a voter with a budget of 16 vote credits can apply 1 vote credit to each of 16 issues. But if they feel strongly about a single issue and apply 4 votes at the cost of 16 credits to a single issue. This will use their entire budget. This also means there is a large incentive to buy and sell votes, although using a strictly secret ballot gives some protection against vote buying as the purchase cannot be verified.
|Number of votes||“Voice Credit” cost|
- Lalley, Steven; Weyl, E. Glen (2017-12-24). "Quadratic Voting: How Mechanism Design Can Radicalize Democracy". Rochester, NY. doi:10.2139/ssrn.2003531.
- "Quadratic Voting". collectivedecisionengines.com. Retrieved 2018-05-22.
- Posner, Eric; Weyl, E. Glen (2018). Radical Markets: uprooting capitalism and democracy for a just society. Princeton. ISBN 9780691177502. OCLC 1030268293.
- 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