Effects of different voting systems under similar circumstances: Difference between revisions

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clean up (AWB), typos fixed: Therefore → Therefore,, However → However, , Chatanooga → Chattanooga, two round → two-round (2)
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m (clean up (AWB), typos fixed: Therefore → Therefore,, However → However, , Chatanooga → Chattanooga, two round → two-round (2))
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{{Tenn voting example}}
 
We can pretend that these are "true preferences" among voters and that this implies how they would vote. However, in an actual election, within a specific voting system, there will be incentives to vote differently (compromising) to improve influence for an acceptable winner.
 
== One-vote systems ==
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*Chattanooga: 15%
 
In a two -round runoff, Knoxville and Chattanooga are eliminated, while Nashville and Memphis advance to the second ballot.
 
The voters from Knoxville and Chattanooga prefer Nashville, because it is closer, over Memphis, so the results of the second ballot would be:
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Nashville would then be declared the winner.
 
Note on strategy: A two -round runoff encourages candidates to unite to make the top two cut. Since Chattanooga and Knoxville both prefer each other second, knowing their divided vote might eliminate them both, they might work together before the election and decide for only Chattanooga to run. That would cause the defeat of Nashville (third place) and Chattanooga could win the final runoff round against Memphis. Something similar would happen with a multi-round elimination ballot, where only the last-place finisher is eliminated.
 
==== Potential for tactical voting ====
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|bgcolor="#ffc0c0"|26
|bgcolor="#ffc0c0"|26
|bgcolor="#e0e0ff"|<strikes>26</strikes> 0
|-
!bgcolor="#ffc0c0"|Chattanooga
|bgcolor="#ffc0c0"|15
|bgcolor="#e0e0ff"|<strikes>15</strikes> 0
|bgcolor="#e0e0ff"|0
|-
!bgcolor="#ffc0c0"|Knoxville
|bgcolor="#ffc0c0"|17
|bgcolor="#ffc0c0"|<strikes>17</strikes> 32
|bgcolor="#ffffc0"|<strikes>32</strikes> 58
|}
 
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!Chattanooga
|bgcolor="#ffc0c0"|15%
|bgcolor="#e0e0ff"|<strikes>15%</strikes> 0
|-
!Knoxville
|bgcolor="#ffc0c0"|17%
|bgcolor="#e0e0ff"|<strikes>17%</strikes> 0
|}
The [[Supplementary Vote]] may be understood both as a special variant of Instant runoff voting (also known as the "alternative vote") in which there are only two rounds of counting and the voter is restricted to expressing only a first and a second preference, and of runoff voting (also known as the two-round system) in which both 'rounds' may occur without the need for a second poll.
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!Chattanooga
|bgcolor="#ffc0c0"|15%
|bgcolor="#e0e0ff"|<strikes>15%</strikes> 0
|-
!Knoxville
|bgcolor="#ffc0c0"|17%
|bgcolor="#e0e0ff"|<strikes>17%</strikes> 0
|}
The [[Sri Lankan supplementary vote]] may be understood both as a special variant of [[Instant-runoff voting]] (also known as the "alternative vote") in which there are only two rounds of counting and the voter is restricted to expressing only a first, second, and third preference, and of [[Two-round system|runoff voting]] (also known as the two-round system) in which both "rounds" may occur without the need for a second poll.
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Assuming each voter votes according to their sincere preferences (for a more sophisticated approach, see below), Nashville and Memphis would receive the most votes and advance to the second round.
 
The second preference of voters from Chattanooga is for Knoxville. However, Knoxville has been eliminated, so the votes must be transferred to the third choice of Chattanooga voters: Nashville, which remains in the race. The second preference of voters from Knoxville is for Chattanooga. Chattanooga has been eliminated so their votes also transfer to their third choice--againchoice—again, Nashville.
 
On the second and final count, therefore, all the votes from the two eliminated candidates transfer to Nashville. Nashville now has more votes than Memphis and so '''Nashville is declared the winner'''. Note that under "conventional" SV the winner would have been Memphis.
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In [[Bucklin voting]] first choice votes are counted first. If one candidate has a majority, that candidate wins. Otherwise the second choices are added to the first choices. Again, if a candidate with a majority vote is found, the winner is the candidate with the most votes in that round. Lower rankings are added as needed.
 
The first round has no majority winner. Therefore, the second rank votes are added. This moves Nashville and ChatanoogaChattanooga above 50%, so a winner can be determined. Since Nashville is supported by a higher majority (68% versus 58%), Nashville is the winner.
 
=== Majority choice approval ===