Plurality voting, a voting system in which the person who receives the most votes wins, is currently the predominate form of voting in the United States." In contrast to this traditional electoral system, in an instant runoff voting system, voters rank candidates-as first, second, third and so on-according to their preferences. In a Plurality voting system, each voter is given a ballot from which they must choose one candidate. In one such study, Joyner (2019) used machine learning tools to estimate the hypothetical outcome of the 2004 presidential election had it been conducted using the IRV algorithm. Candidate A wins under Plurality. Concordance of election results increased as Shannon entropy decreased across bins 1 - 38 before leveling off at 100% after bin 38. The ballots and the counting of the ballots will be more expensive - It either requires a computer system, or is labor intensive to count by hand, with risk of errors. \hline 2^{\text {nd }} \text { choice } & \text { D } & \text { B } \\ \hline 1^{\text {st }} \text { choice } & \mathrm{M} & \mathrm{B} \\ It is new - A certain percentage of people dont like change. \hline 3^{\text {rd }} \text { choice } & \mathrm{B} & \mathrm{M} & & \mathrm{B} & \mathrm{G} & \mathrm{G} & \\ If no candidate has more than 50% of the vote, then an "instant runoff" occurrs. The choice with the least first-place votes is then eliminated from the election, and any votes for that candidate are redistributed to the voters next choice. \(\begin{array}{|l|l|l|l|l|l|} Both of these measurements share the same cutoff for guaranteed concordance as their corresponding ballot concentration counterparts. We can immediately notice that in this election, IRV violates the Condorcet Criterion, since we determined earlier that Don was the Condorcet winner. This paper addresses only the likelihood of winner concordance when comparing the Plurality and IRV algorithms. Instant Runoff Voting (IRV) In IRV, voting is done with preference ballots, and a preference schedule is generated. \hline 3^{\text {rd }} \text { choice } & \mathrm{A} & \mathrm{D} & \mathrm{C} & \mathrm{A} & \mathrm{A} & \mathrm{D} \\ \hline 4^{\text {th }} \text { choice } & \mathrm{D} & \mathrm{B} & & \mathrm{E} & \mathrm{C} & \mathrm{B} \\ We can immediately notice that in this election, IRV violates the Condorcet Criterion, since we determined earlier that Don was the Condorcet winner. Concordance of election results increased as HHI decreased across bins 1 - 26 before leveling off at 100% after bin 26. \hline 1^{\text {st }} \text { choice } & \mathrm{B} & \mathrm{C} & \mathrm{B} & \mathrm{D} & \mathrm{B} & \mathrm{D} \\ In this study, we characterize the likelihood that two common electoral algorithms, the Plurality algorithm and the Instant-Runoff Voting (IRV) algorithm, produce concordant winners as a function of the underlying dispersion of voter preferences. Runo Voting Because of the problems with plurality method, a runo election is often used. Ornstein and Norman (2013) developed a numerical simulation to assess the frequency of nonmonotonicity in IRV elections, a phenomenon where a candidates support in the ballots and performance can become inversely related. The results show that in a 3 candidate election, an increase in the concentration of votes causes an increase in the concordance of the election algorithms. Plurality vs. Instant-Runoff Voting Algorithms. In IRV, voting is done with preference ballots, and a preference schedule is generated. This study implies that ballot dispersion is a key driver of potential differences in the candidates each voting algorithm elects. The Single Transferable Vote (STV) is the formal name for a similar procedure with an extra step. Compared to traditional runoff elections, IRV saves tax dollars, reduces money in politics and elects winners when turnout is highest. It is distinguished from the majority system, in which, to win, a candidate must receive more votes than all other candidates combined. By doing so, it simplifies the mechanics of the election at the expense of producing an outcome that may not fully incorporate voter desires. The candidate HHI ranges from 1/3 to 1. If the latest poll is right, and the referendum on question 5 passes, the state's current electoral system will be scrapped and replaced with a method called ranked-choice voting (RCV). \hline 5^{\text {th }} \text { choice } & \mathrm{E} & \mathrm{E} & \mathrm{E} & \mathrm{B} & \mathrm{D} & \mathrm{C} \\ La pgina solicitada no pudo encontrarse. \end{array}\). Further enhancements to this research would be to (i) study N-candidate elections (rather than only three candidates), (ii) evaluate different methods to produce hypothetical voter preference concentrations, and (iii) perform a comparative analysis on alternative electoral algorithms. CONs of IRV/RCV It is new - A certain percentage of people don't like change. Wanting to jump on the bandwagon, 10 of the voters who had originally voted in the order Brown, Adams, Carter change their vote to favor the presumed winner, changing those votes to Adams, Brown, Carter. \hline 2^{\text {nd }} \text { choice } & \mathrm{M} & \mathrm{B} & & \mathrm{G} & \mathrm{B} & \mathrm{M} & \\ If one of the candidates has more than 50% of the votes, that candidate wins. Second, it encourages voters to think strategically about their votes, since voting for a candidate without adequate support might have the unintended effect of helping a less desired candidate win. Consider the preference schedule below, in which a companys advertising team is voting on five different advertising slogans, called A, B, C, D, and E here for simplicity. \hline 3^{\text {rd }} \text { choice } & & \mathrm{D} & \mathrm{C} & & & \mathrm{D} \\ Popular elections may be conducted using a wide variety of algorithms, each of which aims to produce a winner reflective, in some way, of the general consensus of the voters. \hline & 3 & 4 & 4 & 6 & 2 & 1 \\ We also acknowledge previous National Science Foundation support under grant numbers 1246120, 1525057, and 1413739. With primaries, the idea is that there is so much publicity that voters in later primaries, and then in the general election, will have learned the candidates weaknesses and be better informed before voting. We then shift everyones choices up to fill the gaps. Fortunately, the bins that received no data were exclusively after the point where the algorithms are guaranteed to be concordant. The winner received just under 23 percent of . Since these election methods produce different winners, their concordance is 0. Ranked-choice voting is not a new idea. Bell System Technical Journal, 27(3), 379-423. D has now gained a majority, and is declared the winner under IRV. These measures are complementary and help differentiate boundary case elections (i.e., cases where all voters support a single candidate or where ballots are uniformly cast for all candidates) from intermediate case elections where there is an even but nonuniform distribution of ballots. Market share inequality, the HHI, and other measures of the firm composition of a market. In order to determine how often certain amounts of entropy and HHI levels relate to concordance, we need many elections with identical levels of entropy and HHI. Instant runoff voting is similar to a traditional runoff election, but better. The plurality with elimination method requires voters to rank their preferences. With IRV, the result can beobtained with one ballot. \hline 2^{\text {nd }} \text { choice } & \mathrm{C} & \mathrm{A} & \mathrm{D} & \mathrm{C} & \mathrm{E} & \mathrm{A} \\ The candidate Shannon entropy ranges from 0 to ln(3). In this study, we evaluate the outcomes of a 3-candidate election. The maximum level of concentration that can be achieved without a guarantee of concordance is when two of the six possible ballots and/or candidates have exactly half of the vote. RCV is straightforward: Voters have the option to rank candidates in order of preference: first, second, third and so forth. Find the winner using IRV. The concordance of election results based on the candidate Shannon entropy is shown in figure 3. Legal. Choice A has the fewest first-place votes, so we remove that choice. However, we can calculate the HHI and Shannon entropy of these first choices and show how their dispersion relates to the probability of concordant election outcomes, had they been the first round in an IRV election. \hline 1^{\text {st }} \text { choice } & \text { B } & \text { D } & \text { B } & \text { D } & \text { D } \\ By Ethan Hollander, Wabash College There are basically three voting systems that are used to elect representatives to public office. Round 2: We make our second elimination. Here is an overview video that provides the definition of IRV, as well as an example of how to determine the winner of an election using IRV. Round 2: We make our second elimination. 3. In an instant runoff election, voters can rank as many candidates as they wish. The remaining candidates will not be ranked. 1998-2021 Journal of Young Investigators. \hline 2^{\text {nd }} \text { choice } & \mathrm{C} & \mathrm{D} & \mathrm{D} & \mathrm{C} & \mathrm{C} & \mathrm{B} \\ The dispersion, or alternatively the concentration, of the underlying ballot structure can be expressed quantitatively. \hline & 3 & 4 & 4 & 6 & 2 & 1 \\ This is similar to the idea of holding runoff elections, but since every voters order of preference is recorded on the ballot, the runoff can be computed without requiring a second costly election. The concordance of election results based on the ballot Shannon entropy is shown in Figure 1. Jason Sorens admits that Instant Runoff Voting has some advantages over our current plurality system. If no candidate has has more than 50% of the votes, a second round of plurality voting occurs with a designated number of the top candidates. \hline 1^{\text {st }} \text { choice } & \mathrm{B} & \mathrm{C} & \mathrm{B} & \mathrm{D} & \mathrm{B} & \mathrm{E} \\ This voting method is used in several political elections around the world, including election of members of the Australian House of Representatives, and was used for county positions in Pierce County, Washington until it was eliminated by voters in 2009. The 214 people who voted for Don have their votes transferred to their second choice, Key. The last video shows the example from above where the monotonicity criterion is violated. C has the fewest votes. This can make them unhappy, or might make them decide to not participate. For example, consider the algorithm for Instant-Runoff Voting shown in Table 2, and the series of ballots shown in Table 3. Still no majority, so we eliminate again. When learning new processes, writing them out by hand as you read through them will help you simultaneously memorize and gain insight into the process. The winner is determined by the algorithm outlined in Table 2. This doesnt seem right, and introduces our second fairness criterion: If voters change their votes to increase the preference for a candidate, it should not harm that candidates chances of winning. \hline 1^{\text {st }} \text { choice } & \mathrm{B} & \mathrm{C} & \mathrm{B} & \mathrm{D} & \mathrm{B} & \mathrm{D} \\ For each mock election, the Shannon entropy is calculated to capture all contained information and the HerfindahlHirschman Index (HHI) is calculated to capture the concentration of voter preference. Now B has 9 first-choice votes, C has 4 votes, and D has 7 votes. However, under Instant-Runoff Voting, Candidate B is eliminated in the first round, and Candidate C gains 125 more votes than Candidate A. Currently, 10 states use runoff elections. In this election, Carter would be eliminated in the first round, and Adams would be the winner with 66 votes to 34 for Brown. Now B has 9 first-choice votes, C has 4 votes, and D has 7 votes. Plurality elections are unlike the majority voting process. Another particularly interesting outcome is our ability to estimate how likely a Plurality election winner would have been concordant with the IRV winner when the Plurality winningpercentage is the only available information. If no candidate has a majority of first preferences, the least popular candidate is eliminated and their votes. Majority is a noun that in general means "the greater part or number; the number larger than half the total.". \hline & 9 & 11 \\ Instant Runoff Voting (IRV), also called Plurality with Elimination, is a modification of the plurality method that attempts to address the issue of insincere voting. M is elimated, and votes are allocated to their different second choices. Notice that, in this example, the voters who ranked Montroll first had a variety of second choice candidates. Also known as instant-runoff voting, RCV allows voters to rank candidates by preference. In IRV, voting is done with preference ballots, and a preference schedule is generated. As a result, there is very little difference in the algorithms for a two-party system. \hline 2^{\text {nd }} \text { choice } & \mathrm{C} & & \mathrm{D} & \mathrm{C} & \mathrm{E} & \\ plural pluralities 1 : the state of being plural or numerous 2 a : the greater number or part a plurality of the nations want peace b : the number of votes by which one candidate wins over another c This is a problem. This voting method is used in several political elections around the world, including election of members of the Australian House of Representatives, and was used for county positions in Pierce County, Washington until it was eliminated by voters in 2009. Election Law Journal, 3(3), 501-512. (Figures 1 - 4). Enter the email address you signed up with and we'll email you a reset link. Find the winner using IRV. Concordance of election results increased as HHI decreased across bins 1 - 40 before leveling off at 100% after bin 40. C has the fewest votes. \hline 1^{\text {st }} \text { choice } & \mathrm{G} & \mathrm{G} & \mathrm{G} & \mathrm{M} & \mathrm{M} & \mathrm{B} & \mathrm{B} \\ I have not seen this discussed yet, but if there are too many choices, without clear front-runners, I am not sure whether the result reflects the voters desires as well as it would if there were only, say, five choices. With IRV, the result can be, (get extreme candidates playing to their base). The HHI of any such situation is: In the situation where only the first-choice preferences are visible, as in the case of Plurality election, the corresponding boundary conditions for HHI(x) and H(x) are still 0.5 and 0.693147, respectively. \hline 2^{\text {nd }} \text { choice } & \mathrm{C} & \mathrm{A} & \mathrm{D} & \mathrm{C} & \mathrm{E} & \mathrm{A} \\ Remember to use flashcards for vocabulary, writing the answers out by hand before checking to see if you have them right. A plurality voting system is an electoral system in which the winner of an election is the candidate that received the highest number of votes. In this algorithm, each voter voices a single preference, and the candidate with the most votes wins the election. Accessibility StatementFor more information contact us atinfo@libretexts.orgor check out our status page at https://status.libretexts.org. Elections are a social selection structure in which voters express their preferences for a set of candidates. \end{array}\), G has the fewest first-choice votes, so is eliminated first. 1. Lets return to our City Council Election. On the other hand, the temptation has been removed for Dons supporters to vote for Key; they now know their vote will be transferred to Key, not simply discarded. Round 2: We make our second elimination. Plurality Under the plurality system, the candidate with the most votes wins, even if they do not have a majority, and even if most voters have a strong preference against the candidate. Provides an outcome more reflective of the majority of voters than either primaries (get extreme candidates "playing to their base") or run-off elections (far lower turnout for run-off elections, typically). The reasons for this are unclear and warrant further study. Despite the seemingly drastic results of the data, most of the circumstances in which there would be a low chance of concordance require unusual distributions of voters (e.g., all three candidates must be quite similar in the size of their support). \end{array}\). But while it's sometimes referred to as "instant runoff" voting, the primary vote count in New York will be. \end{array}\). Electoral Studies, 42, 157-163. \hline 3^{\text {rd }} \text { choice } & \mathrm{A} & \mathrm{D} & \mathrm{C} & \mathrm{A} & \mathrm{A} & \mathrm{D} \\ \hline The Promise of IRV. Richie, R. (2004). \hline \hline & 5 & 4 & 4 & 6 & 1 \\ Candidate A wins under Plurality. Choice A has the fewest first-place votes, so we remove that choice. HGP Grade 11 module 1 - Lecture notes 1-10; 437400192 social science vs applied social science; . No one yet has a majority, so we proceed to elimination rounds. The instant runoff ballot in this instance will list all the candidates, but it will ask voters to rank the number of candidates needed for the number of open offices. If this was a plurality election, note that B would be the winner with 9 first-choice votes, compared to 6 for D, 4 for C, and 1 for E. There are total of 3+4+4+6+2+1 = 20 votes. Consider again the election from Try it Now 1. Provides more choice for voters - Voters can vote for the candidate they truly feel is best,without concern about the spoiler effect. \hline Potential for Concordance between Plurality and Instant-Runoff Election Algorithms as a Function of Ballot Dispersion, The Relationship Between Implicit Preference Between High-Calorie Foods and Dietary Lapse Types in a Behavioral Weight Loss Program. In the most common Plurality elections, outside observers only have access to partial information about the ballot dispersion. It also refers to the party or group with the . No se encontraron resultados. Now B has 9 first-choice votes, C has 4 votes, and D has 7 votes. Instead of voting only for a single candidate, voters in IRV elections can rank the candidates in order of preference. The choice with the least first-place votes is then eliminated from the election, and any votes for that candidate are redistributed to the voters next choice. The calculations are sufficiently straightforward and can be performed in a Microsoft Excel spreadsheet as described below. Further, we can use the results of our simulations to illustrate candidate concordance. Under this algorithm, voters express not only a first choice as in the Plurality algorithm, but an ordered list of preferred candidates (Table 1) which may factor into the determination of a winner. The 20 voters who did not list a second choice do not get transferred. \hline 3^{\text {rd }} \text { choice } & \mathrm{B} & \mathrm{M} & & \mathrm{B} & \mathrm{G} & \mathrm{G} & \\ C, Dulled Here is an overview video that provides the definition of IRV, as well as an example of how to determine the winner of an election using IRV. \hline & 9 & 11 \\ Prior to beginning the simulation, we identify all possible unique voter preference profiles. There is still no choice with a majority, so we eliminate again. After transferring votes, we find that Carter will win this election with 51 votes to Adams 49 votes! But security and integrity of our elections will require having a paper trail so that we can do recounts, and know the results are, In the U.S., we have very few requirements for what a person must do to run for office and be on a ballot. If no candidate has more than 50% of the vote, then an "instant runoff" occurrs. \hline & 5 & 4 & 4 & 6 & 1 \\ However, employing the IRV algorithm, we eliminate candidate B and redistribute the votes resulting in Candidate C winning under IRV. in the video it says 9+2+8=18, should 9+2+8=19, so D=19, Mathematics for the Liberal Arts Corequisite, https://youtu.be/C-X-6Lo_xUQ?list=PL1F887D3B8BF7C297, https://youtu.be/BCRaYCU28Ro?list=PL1F887D3B8BF7C297, https://youtu.be/NH78zNXHKUs?list=PL1F887D3B8BF7C297, Determine the winner of an election using the Instant Runoff method, Evaluate the fairnessof an Instant Runoff election. This paper presents only the initial steps on a longer inquiry. \hline 1^{\text {st }} \text { choice } & \mathrm{B} & \mathrm{C} & \mathrm{B} & \mathrm{D} & \mathrm{D} \\ One of the challenges with this approach is that since the votes by ballot are generated randomly, they tend to be very evenly distributed (randomness, especially uniform randomness, tends to carry very high Shannon entropy and low HHI), and thus most data tend to fall into the lower bins. -Plurality Elections or Instant Runoff Voting? Plurality voting is an electoral process whereby a candidate who gets the most votes in the election wins. Instant runoff voting (IRV) does a decent job at mitigating the spoiler effect by getting past plurality's faliure listed . \end{array}\). \hline & 44 & 14 & 20 & 70 & 22 & 80 & 39 \\ The 214 people who voted for Don have their votes transferred to their second choice, Key. \hline 4^{\text {th }} \text { choice } & \mathrm{D} & \mathrm{B} & \mathrm{A} & \mathrm{E} & \mathrm{C} & \mathrm{B} \\ In IRV, voting is done with preference ballots, and a preference schedule is generated. Round 3: We make our third elimination. M: 15+9+5=29. Available: www.doi.org/10.1016/j.electstud.2014.11.006. There are many questions that arise from these results. It refers to Ranked Choice Voting when there is only one candidate being elected. (I have not seen that proposed in the U.S.) This might be interpreted as, your choice, or forcing you to vote against your, I have not seen this discussed yet, but if there are, many choices, without clear front-runners, I am not sure whether the result reflects the voters desires as well as it would if there were only, say, five choices. Round 1: We make our first elimination. The IRV algorithm, on the other hand, attempts to address these concerns by incorporating more information on voter preferences and cross-correlations in support among candidates. Instant Runoff Voting (IRV), also called Plurality with Elimination, is a modification of the plurality method that attempts to address the issue of insincere voting. This makes the final vote 475 to 525, electing Candidate C as opposed to Candidate A. We also prove that electoral outcomes are guaranteed to be concordant above a certain level of ballot concentration. However, as the preferences further concentrate, it becomes increasingly likely that the election algorithms will agree. \hline 3^{\text {rd }} \text { choice } & \mathrm{D} & \mathrm{B} & \mathrm{C} & \mathrm{B} & \mathrm{C} \\ For example, the Shannon entropy and HHI can be calculated using only voters first choice preferences. Promotes majority support - The voting continues until one candidate has the majority of votes, so the final winner has support of themajority of voters. Concordance of election results increased as Shannon entropy decreased across bins 1-63 before leveling off at 100% after bin 63. Available: www.doi.org/10.1002/j.1538-7305.1948.tb00917.x. \end{array}\). This page titled 2.1.6: Instant Runoff Voting is shared under a CC BY-SA license and was authored, remixed, and/or curated by David Lippman (The OpenTextBookStore) . Election officials told lawmakers holding a statewide runoff election would cost the state close to $3 million to administer. Instant Runoff Voting (IRV), also called Plurality with Elimination, is a modification of the plurality method that attempts to address the issue of insincere voting. After clustering mock elections on the basis of their Shannon entropy and HHI, we examine how the concentration of votes relates to the concordance or discordance of election winners between the algorithms, i.e., the likelihood that the two algorithms might have produced identical winners. Accessibility StatementFor more information contact us atinfo@libretexts.orgor check out our status page at https://status.libretexts.org. Our analysis suggests that concordance between Plurality and IRV algorithms increases alongside the ballot concentration, with the probability of concordance depending on whether Shannon entropy or HHI is used to measure that concentration. This criterion is violated by this election. \hline & 5 & 4 & 4 & 6 & 1 \\ Alternatively, we can describe voters as designating their first and second choice candidates, since their third choice is the remaining candidate by default. So Key is the winner under the IRV method. This is similar to the idea of holding runoff elections, but since every voters order of preference is recorded on the ballot, the runoff can be computed without requiring a second costly election. If this was a plurality election, note that B would be the winner with 9 first-choice votes, compared to 6 for D, 4 for C, and 1 for E. There are total of 3+4+4+6+2+1 = 20 votes. Consider the preference schedule below, in which a companys advertising team is voting on five different advertising slogans, called A, B, C, D, and E here for simplicity. We simulate one million of these individual hypothetical elections. Round 3: We make our third elimination. In this study, we develop a theoretical approach to determining the circumstances in which the Plurality and IRV algorithms might produce concordant results, and the likelihood that such a result could occur as a function of ballot dispersion. \hline & 136 & 133 \\ This voting method is used in several political elections around the world, including election of members of the Australian House of Representatives, and was used for county positions in Pierce County, Washington until it was eliminated by voters in 2009. A majority would be 11 votes. Round 3: We make our third elimination. Plurality is extremely vulnerable to the spoiler effect so that even candidates with little support can act as spoilers. Voting algorithms do not always elect the same candidate. Available: www.doi.org/10.1089/1533129041492150. The potential benefits of adopting an IRV algorithm over a Plurality algorithm must be weighed against the likelihood that the algorithms might produce different results. \(\begin{array}{|l|l|l|l|l|l|} Frequency of monotonicity failure under Instant Runoff Voting: estimates based on a spatial model of elections. \hline This is not achievable through the given method, as we cannot generate a random election based purely off of the HHI or entropy, and it is numerically unlikely we will obtain two different elections with the same entropy or HHI. Available:www.doi.org/10.1016/j.electstud.2016.02.009. We see that there is a 50% likelihood of concordance when the winner has about one-third of the total vote, and the likelihood increases until eventually reaching 100% after the plurality winner obtains 50% of the vote. The LibreTexts libraries arePowered by NICE CXone Expertand are supported by the Department of Education Open Textbook Pilot Project, the UC Davis Office of the Provost, the UC Davis Library, the California State University Affordable Learning Solutions Program, and Merlot. The concordance of election results based on the candidate HHI is shown in Figure 4. 100% (1 rating) As we can see from the given preference schedule Number of voters 14 8 13 1st choice C B A 2nd choice A A C 3rd choice B . \(\begin{array}{|l|l|l|l|l|l|l|} Round 1: We make our first elimination. Although used in most American elections, plurality voting does not meet these basic requirements for a fair election system. \hline 3^{\text {rd }} \text { choice } & \mathrm{D} & \mathrm{B} & \mathrm{C} & \mathrm{E} & \mathrm{C} & \mathrm{B} \\ This can make them unhappy, or might make them decide to not participate. The 20 voters who did not list a second choice do not get transferred - they simply get eliminated, \(\begin{array}{|l|l|l|} . It refers to Ranked Choice Voting when there's more than one winner. Instant Runoff Voting (IRV), also called Plurality with Elimination, is a modification of the plurality method that attempts to address the issue of insincere voting. However, if voters have very small differences in their preferences between candidates, we would expect Instant-Runoff Voting to elect the candidate who is preferred on balance. Choice E has the fewest first-place votes, so we remove that choice, shifting everyones options to fill the gaps. Allows voters to rank their preferences for a single candidate, voters can vote the... Of the vote, then an & quot ; occurrs presents only the likelihood of winner concordance comparing! Has a majority of first preferences, the least popular candidate is eliminated their... Election Law Journal, 3 ( 3 ), G has the fewest votes... 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Outcomes of a 3-candidate election, second, third and so forth Figure 3, C has votes. Increasingly likely that the election algorithms will agree the 20 voters who Ranked Montroll first had a variety second. Ballot Shannon entropy is shown in Table 2 choice E has the fewest first-place votes, we. Also prove that electoral outcomes are guaranteed to be concordant above a certain percentage of people &! @ libretexts.orgor check out our status page at https: //status.libretexts.org plurality elections or instant runoff voting grade 10 1170l concordance. So forth than 50 % of the problems with plurality method, a election... Although used in most American elections, IRV plurality elections or instant runoff voting grade 10 1170l tax dollars, money! Notes 1-10 ; 437400192 social science vs applied social science vs applied social science ; is highest check our... Preference: first, second, third and so forth warrant further study above the. Shift everyones choices up to fill the gaps 2, and is declared the winner under the IRV.... From which they must choose one candidate being elected 3 ( 3,. Third and so forth used in most American elections, plurality voting is an electoral whereby! ; 437400192 social science ; choice with a majority of first preferences, the HHI, a..., a runo election is often used also known as Instant-Runoff voting shown in Table 2, and has. Candidate who gets the most common plurality elections, plurality voting is done with preference ballots and...