What is Score Voting?
Score Voting is a single-winner voting system where voters rate candidates on a scale. The candidate with the highest rating wins.
Score Voting highlights:
- Extremely expressive
- No vote splitting or spoilers
- Always vote your honest favorite
- Less spoiled ballots than Plurality and ranked systems
- Results are easy to understand, just like Plurality
- Can easily be used with modern election machines, unlike ranked systems
- Alternate candidates get a more accurate measure of support
Score Voting has voters rate candidates or choices on a scale. This is similar to Internet Movie Database, Amazon, Yelp, or the website Hot or Not. Score Voting is also sometimes referred to as Range Voting because voters rate options along a range of values. The names are interchangeable.
Technical notes: Simplified forms of Score Voting automatically give skipped candidates the lowest possible score for the ballot they were skipped. Other forms have those ballots not affect the candidate’s rating at all. Those forms not affecting the candidates rating frequently make use of quotas. Quotas demand a minimum proportion of voters rate that candidate in some way before that candidate is eligible to win.
Below we have two different Score Voting ballots. The one on the left uses a 0-9 scale. On the right is a simplified version with a 0-2 scale.
Voters score each candidate on the ballot. These ballots can be used with modern election machines. CES board member Jan Kok, an engineer, demonstrates this here. Note that this is not an endorsement of using computers to count votes.
Who uses Score Voting?
The Harvey Milk Democratic Club, the largest Democratic club in San Francisco, uses Score Voting for their endorsements.
The Pirate Party of North Rhine-Westphalia, the most populous of Germany’s 16 states (population: 18 million), uses Score Voting (on a -3 to +3 scale) to elect their Board of Directors. On May 13, 2012, the NRW Pirates won 7.8% of the vote in the state elections, winning 20 of the 237 seats in state parliament. (Their party list had itself been selected via multi-winner Approval Voting.) They subsequently held their first Score Voting Board of Directors election on May 29, 2012. The results of that election are here.
The Pirate Party of Lower Saxony subsequently adopted Score Voting (on a 0-5 scale) to order their party list. The first use was on August 25, 2012.
“Overall the counting proved that we had chosen the right system. We were only slightly slower than we had expected and most people were happy with the result. They felt that with the scoring they could express their will in a very effective way.” - André, Pirate Party Member, Germany
ESPN.com uses Score Voting to rank every NBA player from number 500 to number 1.
Mozilla, the organization that makes the popular Firefox web browser, uses Score Voting to select Mentors for their Mozilla Reps program.
The Fedora Project, a partnership of free software community members from around the globe, uses Score Voting to select their board members.
The Central Co-op, an independent, member-owned natural foods cooperative in Seattle, WA, uses Score Voting for their Inside Trustee Elections.
“It’s easy to understand.” - Webster Walker, Community Outreach Administrator, Central Co-op, Seattle, WA
The San Francisco FrontRunners, a running club, uses Score Voting to select which charity to donate their proceeds to.
NAVA, the North American Vexillological Association, used Score Voting to identify the best and worst flags on the continent.
The Miss America Pageant uses Score Voting to select their finalists.
The cooking shows Iron Chef, Top Chef, and Cupcake Wars all use Score Voting to select their winners.
Both Score and Approval Voting are cardinal systems. Cardinal systems use utility expressions that do not involve ranking. Voters are also permitted to have a say on all the choices. Approval Voting is a simplified form of Score Voting. When voters only use the extremes of the scale, then Score Voting reverts to Approval Voting. Data from a 2007 French study strongly suggest that many voters will use the middle of the scale as well. And to the extent voters use the middle of the scale to vote more honestly, Score Voting provides a better outcome than Approval Voting, on average. (See Bayesian Regret). Score voting, like Approval Voting, doubles the winner utility compared to both Plurality and Instant Runoff Voting. This conclusion considers the strategic voting we see in real life (See Bayesian Regret).