The STAR voting ballot, including recommended instructions and formatting detailsGraphic explaining how STAR Voting works
STAR voting is an electoral system for single-seat elections.[1][2] The name (an allusion to star ratings) stands for "Score Then Automatic Runoff", referring to the fact that this system is a combination of score voting, to pick two finalists with the highest total scores, followed by an "automatic runoff" in which the finalist who is preferred on more ballots wins. It is a type of cardinal voting electoral system.
In STAR, voters are given a score ballot (or ratings ballot) on which each voter scores candidates with a number from 0 up to 5, with 0 representing "worst" and 5 representing "best". The scores for each candidate are then summed, and the two highest-scored candidates are selected as finalists. In the automatic runoff round, the finalist who was given a higher score on a greater number of ballots is selected as the winner.
Usage
The concept was first proposed in October 2014 by Mark Frohnmayer, and was initially called score runoff voting (SRV).[3] The runoff step was introduced in order to reduce strategic incentives in ordinary score voting, such as bullet voting and tactical maximization.[4] STAR is intended to be a hybrid between (rated) score voting and (ranked) instant runoff voting.[5][6]
The first movement to implement STAR voting was centered in Oregon,[7][8] with chapters in Eugene, Portland, Salem, Astoria, and Ashland.[9] In July 2018, supporters submitted over 16,000 signatures for a ballot initiative in Lane County, Oregon, putting Measure 20-290 on the November 2018 ballot.[1][10][11][12] This ballot measure did not pass, with 47.6% of voters voting yes, and 52.4% of voters voting no.[13][14]
In 2019, the Multnomah CountyDemocratic Party adopted STAR for all internal elections.[15][16] A 2020 ballot initiative for the city of Eugene (in which a 54% majority had supported the 2018 county initiative) was attempted, as well as a second attempt at Lane County,[17] and an initiative in Troutdale, Oregon.[18] On July 27, 2020, after the Eugene City Council deadlocked at 4-4 on a vote to refer a measure allowing STAR voting to be used in city elections to the November 2020 ballot, Eugene Mayor Lucy Vinis cast the deciding vote against the referral, meaning that no Eugene ballot measure would be held in 2020.[19]
The Independent Party of Oregon used STAR voting in their 2020 primary election.[20][21][22][23] The Democratic Party of Oregon used STAR Voting for their elections for delegates to the 2020 Democratic convention.[23] In 2022, the Libertarian Party of Oregon authorized STAR voting for its internal elections starting in 2023.[24] In 2024, the city council of Oakridge, Oregon, voted 5-1 to place a STAR voting measure on the November ballot. The measure would have implemented STAR voting for the following three elections before holding a vote on whether to permanently adopt it.[25] However, the measure failed with 46% approval.[26]
Suppose that 100 voters each decided to score from 0 to 5 stars each city such that their most liked choice got 5 stars, and least liked choice got 0 stars, with the intermediate choices getting an amount proportional to their relative distance.
Voter from/ City choice
Memphis
Nashville
Chattanooga
Knoxville
Total
Memphis
210 (42 × 5)
0 (26 × 0)
0 (15 × 0)
0 (17 × 0)
210
Nashville
84 (42 × 2)
130 (26 × 5)
45 (15 × 3)
34 (17 × 2)
293
Chattanooga
42 (42 × 1)
52 (26 × 2)
75 (15 × 5)
68 (17 × 4)
237
Knoxville
0 (42 × 0)
26 (26 × 1)
45 (15 × 3)
85 (17 × 5)
156
The top-two frontrunners are Nashville and Chattanooga. Of the two, Nashville is preferred by 68% (42+26) to 32% (15+17) of voters, so Nashville, the capital in real life, likewise wins in the example. For comparison, traditional first-past-the-post would elect Memphis, even though most citizens consider it the worst choice, because 42% is larger than any other single city. Instant-runoff voting would elect the second-worst choice (Knoxville) because the central candidates would be eliminated early. Under score voting, Nashville would have won, since it had the highest score in the first round. In approval voting, with each voter selecting their top two cities, Nashville would also win because of the significant boost from Memphis residents. A two-round system would have a runoff between Memphis and Nashville, where Nashville would win. In this particular case, there is no way for any single city of voters to get a better outcome through tactical voting; however, Chattanooga and Knoxville voters combined could vote strategically to make Chattanooga win; while Memphis and Nashville voters could defend against that strategy and ensure Nashville still won by strategically giving Nashville a higher rating and/or Chattanooga and Knoxville lower ratings.
Ties
Although tie votes in STAR Voting are rare, as with any voting method, they can occur, especially in elections without many voters. In most cases, ties in STAR voting can be broken by referring back to the ballots themselves for either the scoring or runoff round. Ties in the scoring round are broken in favor of the candidate who was preferred by more voters. Ties in the runoff round are broken in favor of the candidate who was scored higher. Ties which cannot be broken as above are considered a true tie.[27]
Properties
STAR voting satisfies the monotonicity criterion, i.e. raising your vote's score for a candidate can never hurt their chances of winning, and lowering it can never help their chances.[28][29] It also satisfies the resolvability criterion (in both Tideman and Woodall's versions).[citation needed]
There are a number of other voting system criteria it does not satisfy. These include the majority criterion, as it can happen that a candidate does not make it to the runoff, even though he is the first preference of a majority.[30] It does not satisfy the mutual majority criterion, although the more candidates there are in the mutual majority set, the greater the chances that at least one of them is among the two finalists in the runoff, in which case one of them will win. It does not always satisfy reversal symmetry (though it only violates it for exactly three candidates). It also violates participation, consistency; and independence of clones (where any clones of the highest rated candidate may receive almost the same rating and enter the runoff, ahead of the second most popular non-clone). It does not satisfy the later-no-harm criterion, meaning that giving a positive rating to a less-preferred candidate can cause a more-preferred candidate to lose.[31]
↑ D R Woodall, "Monotonicity and Single-Seat Election Rules", Voting matters, Issue 6, 1996. This article calls the monotonicity criterion in question "mono-raise", and also gives other monotonicity criteria that STAR voting fails. For instance, STAR voting violates "mono-raise-delete", defined as "A candidate X should not be harmed if X is raised on some ballots and all candidates now below X on those ballots are deleted from them". In the case of STAR, "deleted" would mean "given the lowest score"; deleting a candidate Y could change the runoff from X vs Y, which X wins, to X vs Z, which Z wins.
↑ "Farewell to Pass/Fail". STAR Voting. Archived from the original on 2018-07-21. Retrieved 2018-07-21. STAR Voting actually fails both Later No Harm and The Favorite Betrayal Criterion - but hear us out! This is actually also desirable. ... We believe it is better for a system to fail two opposing criteria and in doing so mitigate the ways in which it fails both
Approval voting is a single-winner electoral system in which voters mark all the candidates they support, instead of just choosing one. The candidate with the highest approval rating is elected. Approval voting is currently in use for government elections in St. Louis, MO, Fargo, ND, and in the United Nations to elect the Secretary General.
Score voting, sometimes called range voting, is an electoral system for single-seat elections. Voters give each candidate a numerical score, and the candidate with the highest average score is elected. Score voting includes the well-known approval voting, but also lets voters give partial (in-between) approval ratings to candidates.
A Condorcet method is an election method that elects the candidate who wins a majority of the vote in every head-to-head election against each of the other candidates, whenever there is such a candidate. A candidate with this property, the pairwise champion or beats-all winner, is formally called the Condorcet winner or Pairwise Majority Rule Winner (PMRW). The head-to-head elections need not be done separately; a voter's choice within any given pair can be determined from the ranking.
Coombs' method is a ranked voting system. Like instant-runoff (IRV-RCV), Coombs' method is a sequential-loser method, where the last-place finisher according to one method is eliminated in each round. However, unlike in instant-runoff, each round has electors voting against their least-favorite candidate; the candidate ranked last by the most voters is eliminated.
In social choice, the negative responsiveness, perversity, or additional support paradox is a pathological behavior of some voting rules, where a candidate loses as a result of having "too much support" from some voters, or wins because they had "too much opposition". In other words, increasing (decreasing) a candidate's ranking or rating causes that candidate to lose (win). Electoral systems that do not exhibit perversity are said to satisfy the positive response or monotonicitycriterion.
Bucklin voting is a class of voting methods that can be used for single-member and multi-member districts. As in highest median rules like the majority judgment, the Bucklin winner will be one of the candidates with the highest median ranking or rating. It is named after its original promoter, the Georgist politician James W. Bucklin of Grand Junction, Colorado, and is also known as the Grand Junction system.
Ranked Pairs (RP), also known as the Tideman method, is a tournament-style system of ranked voting first proposed by Nicolaus Tideman in 1987.
In social choice, a no-show paradox is a surprising behavior in some voting rules, where a candidate loses an election as a result of having too many supporters. More formally, a no-show paradox occurs when adding voters who prefer Alice to Bob causes Alice to lose the election to Bob. Voting systems without the no-show paradox are said to satisfy the participation criterion.
The majority criterion is a voting system criterion applicable to voting rules over ordinal preferences required that if only one candidate is ranked first by over 50% of voters, that candidate must win.
The Borda count electoral system can be combined with an instant-runoff procedure to create hybrid election methods that are called Nanson method and Baldwin method. Both methods are designed to satisfy the Condorcet criterion, and allow for incomplete ballots and equal rankings.
In single-winner voting system theory, the Condorcet loser criterion (CLC) is a measure for differentiating voting systems. It implies the majority loser criterion but does not imply the Condorcet winner criterion.
Anti-plurality voting describes an electoral system in which each voter votes against a single candidate, and the candidate with the fewest votes against wins. Anti-plurality voting is an example of a positional voting method.
In social choice theory, the best-is-worst paradox occurs when a voting rule declares the same candidate to be both the best and worst possible winner. The worst candidate can be identified by reversing each voter's ballot, then applying the voting rule to the reversed ballots find a new "anti-winner".
The Kemeny–Young method is an electoral system that uses ranked ballots and pairwise comparison counts to identify the most popular choices in an election. It is a Condorcet method because if there is a Condorcet winner, it will always be ranked as the most popular choice.
Later-no-harm is a property of some ranked-choice voting systems, first described by Douglas Woodall. In later-no-harm systems, increasing the rating or rank of a candidate ranked below the winner of an election cannot cause a higher-ranked candidate to lose. It is a common property in the plurality-rule family of voting systems.
Instant-runoff voting (IRV), is a single-winner, multi-round elimination rule that uses ranked voting to simulate a series of runoff elections. In each round, the last-place finisher according to a plurality vote is eliminated, and the votes supporting the eliminated choice are transferred to their next available preference until one of the options reaches a majority of the remaining votes. Instant runoff falls under the plurality-with-elimination family of voting methods, and is thus closely related to rules like the exhaustive ballot and two-round runoff system
Majority judgment (MJ) is a single-winner voting system proposed in 2010 by Michel Balinski and Rida Laraki. It is a kind of highest median rule, a cardinal voting system that elects the candidate with the highest median rating.
There are a number of different criteria which can be used for voting systems in an election, including the following
The sincere favorite or no favorite-betrayal criterion is a property of some voting systems that says voters should have no incentive to vote for someone else over their favorite. It protects voters from having to engage in lesser-evil voting or a strategy called "decapitation".
The Equal Vote Coalition is a nonpartisan American electoral reform group that advocates for voting methods that promote true equality in the vote including STAR Voting, Approval Voting, and Condorcet voting.
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