Talk:1844: Voting Systems

2017-05-31T15:00:31Z

162.158.69.75: /* Consolidate Information */ new section

== Consolidate Information ==

Looks like 2 of us added explanations at the same time. Someone else want to consolidate them and produce a concise explanation?

~blackhat

1844: Voting Systems

2017-05-31T14:58:38Z

162.158.69.75: /* Explanation */

{{comic
| number = 1844
| date = May 31, 2017
| title = Voting Systems
| image = voting_systems.png
| titletext = Kenneth Arrow hated me because the ordering of my preferences changes based on which voting systems have what level of support. But it tells me a lot about the people I'm going to be voting with!
}}

==Explanation==
In this comic, Cueball, White-hat, and Ponytail are discussing voting systems. Cueball mentions three different types: approval voting, instant runoff, and condorcet voting.

'''Approval voting:''' basic voting system in which a voter can select any number of candidates. Each candidate is treated as a separate question "Do you approve of this person winning, yes or no?" The candidate with the most votes wins. [http://electology.org/approval-voting See this for more info]

'''Instant Runoff:''' Also known as Ranked Choice Voting (RCV), instant runoff voting simulates a series of elections until a single candidate holds more than 50% of the votes. Voters rank as many or all of the candidates on the ballot. In the first round, if no candidate has greater than 50% of the votes, the last place candidate is eliminated. If another election were held, voters who chose the eliminated candidate would vote for their second choice (ranked #2 on their ballots). In the simulated second round, that is exactly what is done. Their votes go to their second choice candidates. This process of eliminating the last place candidate and redistributing votes continues until there are two remaining candidates or a candidate has greater than 50% of the vote. [https://en.wikipedia.org/wiki/Instant-runoff_voting Read more here]

Condorcet Method: A Condorcet Method does not refer to a single voting method. It generally refers to a system that allows voters to rank candidates, but specifics may vary. It must fulfill the following requirement: a Condorcet winner is the candidate who would win the majority of the vote in each of the potential head-to-head elections against other candidates. [https://www.opavote.com/methods/condorcet-voting Read more here]

This comic references three types of voting system:

1) [https://en.wikipedia.org/wiki/Approval_voting '''Approval Voting''']: Approval voting is a single-winner electoral system. Each voter may "approve" of (i.e., select) any number of candidates. The winner is the most-approved candidate.

2) [https://en.wikipedia.org/wiki/Instant-runoff_voting '''Instant-Runoff Voting''']: In Instant-Runoff Voting (also known as Ranked Choice or Preferential Voting) voters in elections can rank the candidates in order of preference. Ballots are initially counted for each elector's top choice. If a candidate secures more than half of these votes, that candidate wins. Otherwise, the candidate in last place is eliminated and removed from consideration. The top remaining choices on all the ballots are then counted again. This process repeats until one candidate is the top remaining choice of a majority of the voters.

3) [https://en.wikipedia.org/wiki/Condorcet_method '''Condorcet Method''']: A Condorcet Method election is one that elects the candidate that would win a majority of the vote in all of the head-to-head elections against each of the other candidates, whenever there is such a candidate.

'''Arrow's impossibility theorem''' states that when voters have three or more distinct alternatives (options), no ranked voting electoral system can convert the ranked preferences of individuals into a community-wide ranking.
As a simple illustration, suppose we have three candidates, A, B, and C, and that there are three voters with preferences as follows (candidates being listed left-to-right for each voter in decreasing order of preference):

{| class="wikitable" style="text-align: center;"
! Voter !! First preference !! Second preference !! Third preference
|-
! Voter 1
| A || B || C
|-
! Voter 2
| B || C || A
|-
! Voter 3
| C || A || B
|}

If C is chosen as the winner, it can be argued that B should win instead, since two voters (1 and 2) prefer B to C and only one voter (3) prefers C to B. However, by the same argument A is preferred to B, and C is preferred to A, by a margin of two to one on each occasion. Thus the choice between A and C would not be the same whether the B choice is present or not. This example is referred to as '''Condorcet paradox'''.

The theorem may be interpreted in a way suggesting that no matter what voting electoral system is implemented in a democracy, the resulting democratic choices are equally imperfect.

'''Approval voting''' is a single-winner electoral system. Each voter may "approve" of (i.e., select) any number of candidates. The winner is the most-approved candidate.

'''Instant-runoff voting''' is another single-winner electoral system. Instead of voting only for a single candidate, voters can rank the candidates in order of preference. Ballots are initially counted for each elector's top choice. If a candidate secures more than half of these votes, that candidate wins. Otherwise, the candidate in last place is eliminated and removed from consideration. The top remaining choices on all the ballots are then counted again. This process repeats until one candidate is the top remaining choice of a majority of the voters.

A '''Condorcet method''' is another single-winner electoral system that elects the candidate that would win a majority of the vote in all of the head-to-head elections against each of the other candidates, whenever there is such a candidate. A candidate with this property is called the Condorcet winner. Due to the Condorcet Paradox, there may not be a Condorcet winner in an election with 3 or more candidates.

==Transcript==
:[White Hat, Ponytail and Cueball are all standing. Cueball is talking.]

:Cueball: I prefer approval voting, but if we're seriously considering instant runoff, then I'll argue for a Condorcet method instead.

:[Caption beneath the panel:]
:Strong Arrow's theorem: the people who find Arrow's theorem significant will never agree on anything anyway.

{{comic discussion}}

1800: Chess Notation

2017-02-17T15:44:54Z

162.158.69.75: /* Explanation */

{{comic
| number = 1800
| date = February 17, 2017
| title = Chess Notation
| image = chess_notation.png
| titletext = I've decided to score all my conversations using chess win-loss notation. (??)
}}

==Explanation==
Cueball begins a conversation with Tophat with the non-sequitor declaration that he will be scoring his conversations using chess notation. In Chess there are 3 possible results, a win, a loss, or a draw. Those are denoted respectively 1–0, 0–1, and ½–½. Apparently Cueball believes that since Tophat doesn't care, this is a drawn conversation. The double question marks at the end of the title text indicates the move was a 'blunder'.

==Transcript==
Cueball: "I've decided to score all my conversations using chess win-loss notation."

White Hat: "I don't know or care what that means."

Cueball: "Fine."

White Hat: "Fine."

[Caption below drawing:] "½–½"

{{comic discussion}}

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Talk:1844: Voting Systems

1844: Voting Systems

1800: Chess Notation