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There are 3000 voters (black dots), 3 candidates (colored dots), and voters vote honestly, supporting the candidates who are most similar to them ideologically (nearest distance).
*C (green) is a partisan candidate on the right
*A (blue) is another partisan candidate, this time on the left
*B (orange) is a moderate candidate, and the best representative of the average voter
== FPTP ==
C wins under [[First Past the Post electoral system|first-past-the-post voting]], since A and B split the votes of the left wing of the electorate. (If A hadn't run, then B would have won. If B hadn't run, then A would have won. But since they both ran in the same election, C won instead.)
[[File:2D election example A vs B vs C.png]]
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes|type=rect
Line 19 ⟶ 21:
}}
== IRV ("RCV") / Exhaustive Ballot ==
A wins under [[Instant-runoff voting|Instant-Runoff Voting]] ("Ranked-Choice Voting"), after B is eliminated for not having enough first-preference votes, leaving A and C. (A is slightly closer to the center, so more people in the center support A over C.)
First round is the same as plurality:
[[File:2D election example A vs B vs C.png]]
{{Graph:Chart|width=200|height=150
Line 33 ⟶ 37:
Second round after B is eliminated:
[[File:2D election example A vs C.png]]
{{Graph:Chart|width=200|height=150
Line 41 ⟶ 48:
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
[[W:Exhaustive ballot|Exhaustive ballot]] behaves the same way, since it uses the same elimination rule as IRV, only held using multiple single-mark ballot runoffs instead of using a ranked ballot.
== Top-two runoff / Open primary / Contingent Vote ==
A wins under [[Runoff voting|top-two runoff]] or an [[W:Nonpartisan blanket primary|open primary]]. A and C have the most votes and proceed to the runoff. (None of the candidates gets over 50% in the first round.) A is slightly closer to the center, so more people in the center support A over C in the runoff.
First round is the same as plurality:
[[File:2D election example A vs B vs C.png]]
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes [%]|type=rect
|x=A, B, C
|y=34.37, 28.70, 36.93
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
Second round after B is eliminated:
[[File:2D election example A vs C.png]]
{{Graph:Chart|width=200|height=150
|xAxisTitle=Candidates|yAxisTitle=Votes [%]|type=rect
|x=A, B, C
|y=53.97, 0.00, 46.03
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
[[W:Contingent vote|Contingent vote]] behaves the same way, except the runoff election is held automatically based on ranked ballots.
== Score ==
[[File:2D election example Scores for A, B, C.png|800x800px]]
B wins under [[Score Voting]] (with normalized ballots), as they are the highest-rated overall by the voters. ▼
▲B wins under [[Score Voting]] (with normalized ballots), as they are the highest-rated overall by the voters. (Dark-colored voters gave that candidate a maximum score, white-colored voters gave them a minimum score.)
{{Graph:Chart|width=200|height=150
Line 58 ⟶ 97:
A vs B:
[[File:2D election example A vs B.png]]
{{Graph:Chart|width=200|height=150
Line 65 ⟶ 106:
|colors=#1f77b4, #ff7f0e, #2ca02c
}}
B vs C:
[[File:2D election example B vs C.png]]
{{Graph:Chart|width=200|height=150
Line 78 ⟶ 122:
== STAR ==
B also wins under [[STAR voting|STAR Voting]]. The first round is the same as Score, so the top-two winners are A and B (since A is slightly closer to the center than C)
[[File:2D election example Scores for A, B, C.png|800x800px]]
{{Graph:Chart|width=200|height=150
Line 88 ⟶ 134:
B is then preferred over A by a 66% majority.
[[File:2D election example A vs B.png]]
{{Graph:Chart|width=200|height=150
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