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selling IRV
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Put this the other way, Approval Voting is a restictive version of Instant Runoff Voting where instead of having N different ranks for N candidates, you are restricted to 2 different ranks for N candidates.
Put this the other way, Approval Voting is a restictive version of Instant Runoff Voting where instead of having N different ranks for N candidates, you are restricted to 2 different ranks for N candidates.

== selling IRV ==

Hi Syd1435,

I'm moving your discussion of Approval voting's flaws to the talk page for two reasons (1) because it really looks like you're actively trying to plug IRV [instead of dispassionately describing the flaws in AV] (2) the tone of the content is really a lot more conversational than it is encyclopedic. Let's work together to bring the most useful content from your contributions back to the article. Best, -- [[User:Kowey|Kowey]] 08:55, 16 Oct 2004 (UTC)

P.S. I will confess that I am partial to AV myself, so we should also get help from a more neutral 3rd party.


----

* In an Approval Vote election, the total number of approvals will add up to more than 100% of the number of voters, which may appear to some people as a breech of the "One Man One Vote" principle. It is not a breech, but how does one argue that it is not a breech?

* Suppose that a voter approves of candidates B and C; but approves of candidate B more than C. How does he cast his votes?
** If he approves of only B, the lack of an approval vote for C may let A in.
** If he approves of both B and C, then he has failed to express his preference for B over C.
** It is thus impossible to simultaneously approve of two candidates which preferring one over the other.
** Approval voting suffers the disadvantage that all approvals are of equal weight, even when the vote wishes to express unequal approvals.


* These two problems are resolved with Instant Runoff Voting.
** With IRV, the total number of votes for each candidate at every stage of the count equals the number of votes orignally cast.
** If a votes put B first, C second and A third, then the full value of his vote is set against B in the first round. Depending on how B and C score against eachother, either the second preferences of C go to B, or the second preferences of B go to C. No votes need be lost in the struggle between like minded B and C against the common enemy A.
** In military terms, there is no "Division of Force" when a voter preferences B before C. No matter whether a votes remains with its original choice, or is redistributed to a lower choice, that vote always retains its full value, one man, one vote, one value.

* There is a problem with Instant Runoff Voting that in practice is no longer a problem.
** With Approval Voting, Limited Voting, and the like, when a computer is used to tally the results, only the total score for each candidate need be recorded. This requires only a small Commodure 64 computer with 64k of memory.
** With Instant Runoff Voting, it is necessary to store an image of every ballot; it there are N ballots, and M candidates per ballot, then a Pentium computer with N * M bytes or even double bytes of memory is required.
** It can also be represented with much less memory. Just as the example above represented many voters with just four columns, you can get my with just counting how many ef each *unique* ballot exists. You only need M * (M!) entries, each entry able to count up to N. For M=4 candidates, this comes to 96 entries. For M=10 candidates, this comes to about 36 mega-entries.
** If Department of Elections only has Commodore 64 computers at its disposal, then a computerised IRV may be out of the question.
** A computerised count of and IRV election would also take much more time to process than an Approval Voting election.
** How many people still use Commodore 64 computers?

==Disadvanges with CAV sample ballot==

The [http://www.ApprovalVoting.org/ Citizens for Approval Voting] website uses the following ballot paper as its logo:

**[YES] Jefferson - a great president
**[NO ] Stalin - a tyrant
**[YES] Madison - a great president
**[YES] Washington - a great president

Clearly, it does not matter which of these three great presidents wins, so long as Stalin loses.

But suppose the ballot was revised as follows:

**[YES] Jefferson - a great president
**[NO ] Stalin - a tyrant
**[YES] Madison - a great president
**[ ? ] [[Warren G. Harding]] - a ROTTEN president

Now the choice is less clear. We would want even Warren G. Harding to beat Stalin, but either Jefferson or Madison to beat Harding. This example shows a fundimental weakness of Approval Voting. Cumulative Voting does better, and Instant Runoff Voting better still.

Put simply, Approval Voting cannot simultaneously approve of multiple candidates and choose between them.

An even more telling ballot would be to place Stalin against the three worst presidents.

==Instant Runoff Equivalent of Approval Voting==
Approval Voting can be converted into a form of Instant Runoff Voting by replacing YES with "1" and NO with "2"

-----------------------------------------------------------------------------
* [2] Joe Smith ----- Greens.
* [1] Henry Ford ---- Rural Republican
* [2] Jane Doe ------ Democrat
* [2] Fred Rubble --- Reform
* [1] Mary Hill ----- City Republican
-----------------------------------------------------------------------------

Note how the numbers "1" and "2" are repeated.

If a voter desires to preference Ford ahead of Hill, while supporting both these Republicans against all others, then that voter would need to use the numbers "1", "2" and "3".

This "1" = "FULL YES", "2" = "PART YES", "3" = "NO"

-----------------------------------------------------------------------------
* [3] Joe Smith ----- Greens.
* [1] Henry Ford ---- Rural Republican
* [3] Jane Doe ------ Democrat
* [3] Fred Rubble --- Reform
* [2] Mary Hill ----- City Republican
-----------------------------------------------------------------------------

It would not be Rocket Science to devise a (computerised) system to allow a voter to use either Approval Voting or Instant Runoff Voting in the same election.

-----------------------------------------------------------------------------
* [3] Joe Smith ----- Greens.
* [1] Henry Ford ---- Rural Republican
* [4] Jane Doe ------ Democrat
* [5] Fred Rubble --- Reform
* [2] Mary Hill ----- City Republican
-----------------------------------------------------------------------------

A convential Instant Runoff Voting requires each square to be filled in by different consequtive numbers, which helps the electoral officials check for errors.

==Multiple winners==
Approval voting can be extended to multiple winner elections, either as '''block approval voting''', a simple variant on [[block voting]] where each voter can select an unlimited number of candidates and the candidates with the most approval votes win, or as ''[[proportional approval voting]]'' which seeks to maximise the overall satisfaction with the final result using approval voting.

A disadvantage of multiple winner voting, is that if there are N vacancies, voters must vote for N candidates, which is like N First Past the Post votes in parallel. The result if often a clean sweep by one major party or the other.

[[Limited Voting]] allows each voter M votes for N vacancies, where M < N, which reduces the likely of a clean sweep.

[[Cumulative Voting]] allows each voter M votes for N vacancies, where M <= N, but the voter can allocate those votes 1 each for M candidates or M votes for just 1 candidate, or something in between.
----

Revision as of 08:55, 16 October 2004

It is easily reversed as disapproval voting where a choice is disavowed, as is already required in other measures in politics (e.g. representative recall).

I don't see why approval voting is any different than any other system for "disapproval". The case cited (representative recall) is not even a single-winner contest. (throw all the bums out :-). It is a single-candidate contest if anything.... I propose dropping that text. NealMcB 18:10, 2004 Apr 29 (UTC)


Reads well now. The point about approval and preference voting both being single-vote systems is now there, but no hierarchy of 'this is a type of that' is anywhere in the descriptions of the voting systems themselves, which is fine, except for disapproval as a variant of approval, which seems the only clear inverse. 15:02, 2003 Jan 17

There was an earlier article here once, but it must have been censored.


Under Approval_voting#Potential_for_Tactical_voting I don't like this statement:

A good strategy is to vote for every candidate the voter prefers to the leading candidate, and to also vote for the leading candidate if he is preferred to the current second-place candidate. When all voters follow this strategy, the Condorcet winner is almost certain to win.

It is an opinion statement and I don't know what qualifications should be made for it. Who says this is a good strategy? How do we measure the "leading candidate"? Is that an approval measure or a plurality measure?!

I've done my own thoughts on Approval Voting and I judge:

A good strategy is to vote for the same candidate you would vote for in a plurality race, and also any candidates you prefer more (ignoring any assumption that those candidates can't win).

This stategy is more practical, and is MUCH more likely to be used, even if it doesn't help the Condorcet Winner.

It would merely allow weak candidates a fair measure of support (approval) without throwing the election against a preferred stronger candidate. Approval offers little to voters in a strong three-way race when the top leader is not predictable. Then approval is only useful as a maximal power "negative vote" against feared competitor(s). (Voting A=1,B=1,C=0 in approval is mathematically equivalent to A=0,B=0,C=-1)

I won't change anything for now, but I appreciate opinions. I accept the existing "good strategy" statement as "Good strategy to elect a Condorcet Winner".

Does anyone else have a problem with the existing "good strategy" statement? Any suggestions for changes?

Thanks! --Tomruen 00:02, 2 Jun 2004 (UTC)

The problem with your phrase is that the vote in a tactical vote in a plurality race may also depend on identifying the leading candidates in a plurality race, the leading candidates may be different under different rules and the information may not be avialable on how others might vote in a plurality race. For those who wish to vote in a way which is unlikely to affect the result, tactical voting advice is unnecessary, and I think the current text makes reasonable sense - the leading candidate obviously means in an approval measure. --Henrygb 23:16, 26 Jun 2004 (UTC)
Hmmm... my first assumption was "leading candidate" meant leading in a single-vote count since it is pretty much meaningless to poll voters with approval votes in a poll. Approval polling is too strongly open to manipulation, even unorganized manipulation - individuals playing around for fun or profit. I accept the same argument exists with single-vote counts, but people still want their true favorite to poll well and are less likely to play unless they really have no preference. --Tom Ruen 05:37, Jun 27, 2004 (UTC)

My question is why approval voting is single winner only. Is it called something else when the top n candidates are elected? --Henrygb 23:16, 26 Jun 2004 (UTC)

Approval certainly could be used for multiwinner elections and doesn't have or need any different name. In practice there's less reason to need it. The "standard" multiwinner election method is called Plurality-at-large or Bloc-voting which allows as many votes as candidates. It's less often people would want to "overvote" with multiple winners except as a defensive vote against one or more most disliked candidates. A more likely vote in plurality-at-large is voting for less candidates than winners because you don't want your lower choices to defeat higher ones.
Actually multiwinner Approval elections are an attractive idea - but only when candidates are truly evaluated independently - that is if the number of winners can be variable and the approval rating needed is fixed before the election.
For example a great application would be a poll for which ALL candidates with more than 15% approval are included in a presidential debate. That's a very valid poll since you know the more you vote for the more winners there will be and your vote for a second favorite CAN'T hurt the chances of winning for a first favorite. --Tom Ruen 05:37, Jun 27, 2004 (UTC)

Approval Voting and the Florida 2000 Butterfly Ballot.

Some thoughts:

  • If Approval Voting had been in force in Florida 2000, then the mistakenly double marked ballots (for Gore and Buchanan) would still have counted. No votes would have been voided. Gore would have got all his genuine votes, while Buchanan was so far behind it would not have mattered it he got some bonus or unintended approval votes.
  • Does Approval Voting comply with "one man one vote"? Yes it does, because any Buchanan votes do not really matter because he was so far behind, and Gore only ever recieves "one useful vote per voter".
  • Has Approval Voting ever actually been used anywhere?
  • The biggest disadvantage of Approval Voting may be that it distorts the election statistics - the total number of votes may appear to add up to more than 100%. Something would need to be done to "normalise" the results.
  • If the votes in an Approval Vote contest add up to more than 100% turnout, how does convince the public that the election has not be tampered with? That might be a hard sell!
  • If 999 Nader voters had approved of Gore, Gore would have beaten Bush.
  • If 999 Buchanan voters had also approved of Bush, Bush would still have won.
  • Note that there were 3rd Party candidates spoiling things on both sides.

Syd1435 09:23, 2004 Oct 4 (UTC)

The dilemma with Approval Voting

Suppose one side of politics is a permanent Coalition, say City Republicans and Rural Republicans, and an election is being held using Approval Voting.

  • If you do not mind which kind of Republican gets in, you approve of both kinds.
  • But say for some reason or another, you would much prefer the Rural Republican to get elected - how then do you fill in your Ballot?
  • Answer, you must approve of the RR candidate and disapprove of the CR candidate.
  • Suppose there are other voters who prefer the City Republican candidate.
  • Taken together, the two Republican candidates will lose a few votes compared to the sole Democratic candidate.
  • There is thus a dangerous split in the Republican camp, albeit a modest one.
  • This illustrates a flaw in Approval Voting, because all approvals have the same value, when in practice, some variation in the approval rating is desirable.

What is needed is some kind of intermediate approval level. Here is a sample ballot paper, to enable both Republicans to be approved, but with one preferred to the other. Then all Republican votes count toward beating the common enemy.


  • [3] Joe Smith ----- Greens.
  • [1] Henry Ford ---- Rural Republican
  • [3] Jane Doe ------ Democrat
  • [3] Fred Rubble --- Reform
  • [2] Mary Hill ----- City Republican

Notes:

  • [1] = 1st preference Approval (YES-FULL)
  • [2] = 2nd preference Approval (YES-PART)
  • [3] = Disapproval............ (NO)

Note that the Modified Approval Voting with variable levels of preference is starting to look like Instant Runoff Voting.

Put this the other way, Approval Voting is a restictive version of Instant Runoff Voting where instead of having N different ranks for N candidates, you are restricted to 2 different ranks for N candidates.

selling IRV

Hi Syd1435,

I'm moving your discussion of Approval voting's flaws to the talk page for two reasons (1) because it really looks like you're actively trying to plug IRV [instead of dispassionately describing the flaws in AV] (2) the tone of the content is really a lot more conversational than it is encyclopedic. Let's work together to bring the most useful content from your contributions back to the article. Best, -- Kowey 08:55, 16 Oct 2004 (UTC)

P.S. I will confess that I am partial to AV myself, so we should also get help from a more neutral 3rd party.



  • In an Approval Vote election, the total number of approvals will add up to more than 100% of the number of voters, which may appear to some people as a breech of the "One Man One Vote" principle. It is not a breech, but how does one argue that it is not a breech?
  • Suppose that a voter approves of candidates B and C; but approves of candidate B more than C. How does he cast his votes?
    • If he approves of only B, the lack of an approval vote for C may let A in.
    • If he approves of both B and C, then he has failed to express his preference for B over C.
    • It is thus impossible to simultaneously approve of two candidates which preferring one over the other.
    • Approval voting suffers the disadvantage that all approvals are of equal weight, even when the vote wishes to express unequal approvals.


  • These two problems are resolved with Instant Runoff Voting.
    • With IRV, the total number of votes for each candidate at every stage of the count equals the number of votes orignally cast.
    • If a votes put B first, C second and A third, then the full value of his vote is set against B in the first round. Depending on how B and C score against eachother, either the second preferences of C go to B, or the second preferences of B go to C. No votes need be lost in the struggle between like minded B and C against the common enemy A.
    • In military terms, there is no "Division of Force" when a voter preferences B before C. No matter whether a votes remains with its original choice, or is redistributed to a lower choice, that vote always retains its full value, one man, one vote, one value.
  • There is a problem with Instant Runoff Voting that in practice is no longer a problem.
    • With Approval Voting, Limited Voting, and the like, when a computer is used to tally the results, only the total score for each candidate need be recorded. This requires only a small Commodure 64 computer with 64k of memory.
    • With Instant Runoff Voting, it is necessary to store an image of every ballot; it there are N ballots, and M candidates per ballot, then a Pentium computer with N * M bytes or even double bytes of memory is required.
    • It can also be represented with much less memory. Just as the example above represented many voters with just four columns, you can get my with just counting how many ef each *unique* ballot exists. You only need M * (M!) entries, each entry able to count up to N. For M=4 candidates, this comes to 96 entries. For M=10 candidates, this comes to about 36 mega-entries.
    • If Department of Elections only has Commodore 64 computers at its disposal, then a computerised IRV may be out of the question.
    • A computerised count of and IRV election would also take much more time to process than an Approval Voting election.
    • How many people still use Commodore 64 computers?

Disadvanges with CAV sample ballot

The Citizens for Approval Voting website uses the following ballot paper as its logo:

    • [YES] Jefferson - a great president
    • [NO ] Stalin - a tyrant
    • [YES] Madison - a great president
    • [YES] Washington - a great president

Clearly, it does not matter which of these three great presidents wins, so long as Stalin loses.

But suppose the ballot was revised as follows:

    • [YES] Jefferson - a great president
    • [NO ] Stalin - a tyrant
    • [YES] Madison - a great president
    • [ ? ] Warren G. Harding - a ROTTEN president

Now the choice is less clear. We would want even Warren G. Harding to beat Stalin, but either Jefferson or Madison to beat Harding. This example shows a fundimental weakness of Approval Voting. Cumulative Voting does better, and Instant Runoff Voting better still.

Put simply, Approval Voting cannot simultaneously approve of multiple candidates and choose between them.

An even more telling ballot would be to place Stalin against the three worst presidents.

Instant Runoff Equivalent of Approval Voting

Approval Voting can be converted into a form of Instant Runoff Voting by replacing YES with "1" and NO with "2"


  • [2] Joe Smith ----- Greens.
  • [1] Henry Ford ---- Rural Republican
  • [2] Jane Doe ------ Democrat
  • [2] Fred Rubble --- Reform
  • [1] Mary Hill ----- City Republican

Note how the numbers "1" and "2" are repeated.

If a voter desires to preference Ford ahead of Hill, while supporting both these Republicans against all others, then that voter would need to use the numbers "1", "2" and "3".

This "1" = "FULL YES", "2" = "PART YES", "3" = "NO"


  • [3] Joe Smith ----- Greens.
  • [1] Henry Ford ---- Rural Republican
  • [3] Jane Doe ------ Democrat
  • [3] Fred Rubble --- Reform
  • [2] Mary Hill ----- City Republican

It would not be Rocket Science to devise a (computerised) system to allow a voter to use either Approval Voting or Instant Runoff Voting in the same election.


  • [3] Joe Smith ----- Greens.
  • [1] Henry Ford ---- Rural Republican
  • [4] Jane Doe ------ Democrat
  • [5] Fred Rubble --- Reform
  • [2] Mary Hill ----- City Republican

A convential Instant Runoff Voting requires each square to be filled in by different consequtive numbers, which helps the electoral officials check for errors.

Multiple winners

Approval voting can be extended to multiple winner elections, either as block approval voting, a simple variant on block voting where each voter can select an unlimited number of candidates and the candidates with the most approval votes win, or as proportional approval voting which seeks to maximise the overall satisfaction with the final result using approval voting.

A disadvantage of multiple winner voting, is that if there are N vacancies, voters must vote for N candidates, which is like N First Past the Post votes in parallel. The result if often a clean sweep by one major party or the other.

Limited Voting allows each voter M votes for N vacancies, where M < N, which reduces the likely of a clean sweep.

Cumulative Voting allows each voter M votes for N vacancies, where M <= N, but the voter can allocate those votes 1 each for M candidates or M votes for just 1 candidate, or something in between.