Asset voting: Difference between revisions
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'''Asset voting''' is used to refer to a voting system in which votes are considered as "assets" given to candidates. If no candidate gets more than the winning threshold (i.e., a majority, in the [[Single-winner voting system|single winner]] case; generally speaking, a [[Droop quota|Droop]] or Hare Quota), then the candidates can redistribute "their" votes to other candidates until a winner exists. Variations exist with different constraints on transfers - for example, the candidate with the fewest votes might be forced to redistribute their votes first. There need not be any threshold either i.e. for however many seats there are to be filled, for that number of candidates with the most votes, they are elected. This variation means that, in this single-winner example:
51 A
49 B
10 C
Candidate C can't prevent A from winning by denying them a Droop quota, since A has the most votes overall.
Asset voting was invented in 1874 by [[w:Lewis Caroll|Lewis Caroll]] (Charles Dodgson), and independently reinvented and named by Forest Simmons and Warren Smith.<ref>{{Cite web|url=https://www.rangevoting.org/AssetCLD.html|title=Asset voting was invented by Lewis Carroll (Charles L. Dodgson)!|website=RangeVoting.org|access-date=2019-03-02}}</ref><ref>{{Cite journal|url=http://www.rangevoting.org/BlackCarrollAER2.pdf|first=Duncan|last=Black|title=Lewis Carroll and the Theory of Games|journal=The American Economic Review|volume=59|issue=2|date=May 1969|pp=206-210}}</ref>
If used as a [[Multi-Member System|multi-winner voting method]], it obeys most [[PSC|proportionality criteria]], if the requisite assumptions about coalitions are extended to include candidates as well as voters. For example, since Asset allows a negotiator or group of negotiators who hold a certain number of Droop Quotas of votes to guarantee the election of up to that number of their preferred candidates (see [[SNTV]]), if the negotiators follow voter preferences then proportionality for Droop solid coalitions is satisfied. In such use, it is similar to [[delegable proxy]] systems except that, unlike such systems, it has public elections only at regularly scheduled intervals (proxies are not "revocable") and elects a fixed number of representatives with equal power.
Asset always picks a winner or winner set that is in the [[Smith set|Smith Set]] based on negotiators' preferences (which is not necessarily the same as the voters' preferences, since the negotiators may be corrupt, change preferences mid-negotiation, not know the voters' full preferences, etc.) if the negotiators are given enough time to negotiate, are honest with each other in their negotiating moves, and don't attempt to strategically alter their preferences,{{Dubious|date=2019-12}} meaning that if the negotiators have discussed every relevant permutation of winners or winner sets, Asset will always produce an outcome that can earn more votes from the negotiators during the negotiations than any other possible outcome, unless certain outcomes earn more votes than each other in a [[Condorcet paradox|Condorcet cycle]], in which case one of those cycling outcomes will win.
Example:
3: A>B>C
3: B>C>A
3: C>A>B
4: D
D starts out with the most votes in the negotiation, but the ABC bloc is a [[mutual majority]], so they have an incentive to put their 9 votes behind one of ABC because they prefer any of them to D winning. In general, the idea is that because Smith candidates [[pairwise beat]] non-Smith candidates, this means that by definition more voters have an incentive to elect Smith candidates than non-Smith candidates. This has interesting extensions to the PR case (see [[Condorcet PR]]), because voters must sometimes keep their vote with a favorite candidate to make their favorite win, preventing them from also supporting their 2nd choice to beat their 3rd choice.
Asset can, under ideal conditions in the multiwinner case, render many [[Free riding|free-riding]] strategies needless; this is because, in some sense, the negotiators can do vote management themselves. Consider the example of three parties, A, B and C, where 51 voters vote for B candidates, 49 vote for A candidates, and 10 for C candidates, and there are 5 seats to be elected. Supposing every voter gives maximal support to all of the candidates of their chosen party, and no support for any other candidate, Party B will win 3 seats in most PR methods. However, if the 49 A voters divide themselves as evenly as possible between 3 of their candidates (17 of them bullet vote the first, 16 each bullet vote the second and third candidates), and a Droop quota is spent every time someone is elected in the PR method, then Party A will be able to win 3 seats instead. With Asset, the B candidates can agree to divide their 51 votes evenly between 3 of them (17 each), ensuring that their candidates will be 3 of the 5 candidates with the most votes when the negotiations end and thus win. <ref name="The Center for Election Science 2019">{{cite web | title=Different reweighting for RRV and the concept of Vote Unitarity | website=The Center for Election Science | date=2019-06-29 | url=https://forum.electionscience.org/t/different-reweighting-for-rrv-and-the-concept-of-vote-unitarity/201/92 | access-date=2020-02-19}}</ref>
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Note however that free riding still can work if a voter honestly supports both a candidate with a small base and a candidate with the same small base combined with other bases, as the voter may wish to give their vote to the first candidate to elect them and hope the other bases will elect the second candidate, giving the voter two rather than only one of their preferred candidates. This type of free riding can lead to popular candidates losing to candidates equally preferred to them by smaller groups of voters if too many voters attempt it.
Asset Voting also has [[Sequential Asset Voting|sequential]] and Bloc versions of itself, which are generally less proportional and more majoritarian than regular Asset in the multiwinner cases (with Bloc Asset, a majority can win every seat). All of these various forms of Asset Voting can be [[Algorithmic Asset Voting|algorithmized]], and under certain (relevant) assumptions, become some type of Condorcet or Condorcet PR method.
== References ==
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