PAL representation: Difference between revisions

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==Example==
==Example==
Imagine that Tennessee is having an election on where to locate 3 public universities (and not, as it says below, the capital).


{{Tenn_voting_example}}


[[Image:Tennessee map for voting example.svg|right|500px|Tennessee's four cities are spread throughout the state]]
Imagine that there are two candidate locations in Memphis, and one in each of the other cities. Also imagine that Chatanooga and Knoxville band together to form the "Eastern party". Memphis voters prefer Memphis, then Nashville then "the Eastern party except for Knoxville" (that is, Chatanooga); while Nashville voters prefer the Eastern party (without distinctions) and then Memphis.

magine that Tennessee is having an election on where to locate 3 public universities. The population of Tennessee is concentrated around its four major cities, which are spread throughout the state. For this example, suppose that the entire [[electorate]] lives in these four cities, and that everyone wants to live as near as many universities as possible.

The candidate sites for the university are:
* {{wp|Memphis}}, the state's largest city, with 42% of the voters, but located far from the other cities
:* Site 1
:* Site 2
* {{wp|Nashville}}, with 26% of the voters, near the center of Tennessee
* The "Eastern Party", composed of:
:* {{wp|Knoxville}}, with 17% of the voters
:* {{wp|Chattanooga}}, with 15% of the voters

The preferences of the voters would be divided like this:

{| class="wikitable"
! width=25% style="background-color: #ffdddd" | 42% of voters<br /><small>(close to Memphis)</small>
! width=25% style="background-color: #ccffcc" | 26% of voters<br /><small>(close to Nashville)</small>
! width=25% style="background-color: #ddddff" | 15% of voters<br /><small>(close to Chattanooga)</small>
! width=25% style="background-color: #ffeedd" | 17% of voters<br /><small>(close to Knoxville)</small>
|-
|
# '''Memphis 1'''
# Rest of Memphis party:
:* Memphis 2
# Nashville
# Eastern party
:* Chattanooga
:* (Knoxville not approved)
|
# '''Nashville'''
# Eastern party:
:* Chattanooga
:* Knoxville
# Memphis party
|
# '''Chattanooga'''
# Rest of Eastern Party:
:* Knoxville
# Nashville
# Memphis party
|
# '''Knoxville'''
# Rest of Eastern Party:
:* Chattanooga
# Nashville
# Memphis party
|}



The quota is 25%. Since both Memphis (site 1) and Nashville are over the quota, both are elected first. Memphis votes are multiplied by 17/42 and transferred to Memphis site 2, and Nashville votes are multiplied by 1/26 and then split evenly between Chatanooga and Knoxville. Totals are now:
The quota is 25%. Since both Memphis (site 1) and Nashville are over the quota, both are elected first. Memphis votes are multiplied by 17/42 and transferred to Memphis site 2, and Nashville votes are multiplied by 1/26 and then split evenly between Chatanooga and Knoxville. Totals are now:

Revision as of 22:20, 23 October 2011

PAL (Proportional, Accountable, Local) representation is a system for electing a legislature, such that ballot secrecy is preserved but each voter can know who their representative is. It's a proportional system, but designed to be a gentle change from a single-member-district system; districts can remain unchanged, and if single-member districts are giving fair proportions from cohesive parties, PAL representation will elect exactly the same members. The difference is that most representatives will represent multiple districts, and each district will have multiple representatives (one from each winning party). Thus, whereas currently only 60-70% of US voters voted for their representative, and many of those because they have no choice, with PAL voting over 80% overall, and over 95% in large states, would be guaranteed have a representative whom they'd supported directly or indirectly.

The basic idea is:

  • Candidates pre-announce their rank-ordering of the parties (starting with their own party) and may optionally approve/disapprove within each party candidates. Their votes will never be transferred to disapproved candidates.
  • Voters may vote on the candidates in their or nearby districts, or write in candidates from farther off. Votes are delegated by default but optionally, voters may refuse to delegate or vote approval-style.
  • Each delegated ballot is transformed into the pre-announced vote of the candidate it supports.
  • A legislature is elected by a version of STV (with fractional transfers and a Droop quota.)
  • Each district "drafts" one member of each elected party from the elected slate.
  • Your representative is the member of the party you voted for who is representing your district.

Full Procedure

  • Candidates pre-announce their rank-ordering of the parties (starting with their own party) and may optionally disapprove of any other candidates.
  • Voters may vote on the candidates in their or nearby districts, or write in candidates from farther off.

First, to simplify the ballots, the population is separated into a "district" for each seat, and "districts" are grouped into sets of 2 or 3 "co-districts". The ballot for each district lists the incumbents and candidates from that district in a larger font, and the candidates from its co-districts below that in a smaller font. Write-ins may be used to vote for candidates from other districts not listed on the ballot, so the districts only matter for ballot simplicity (Voters do not want to have a ballot with many dozens of candidates on it, but write-ins allow full freedom for those voters who want it). Larger parties will usually run one candidate per district; smaller parties may just run one candidate per co-district set.

  • The quota Q is set to the Droop Quota; that is, to the rational number (V+1)/(S+1), where V is valid votes and S is seats.
  • Each vote is transformed into the pre-announced party preference order and individual approvals/disapprovals of the candidate it chooses.
  • A legislature is elected by a version of STV.
  • Delegated votes first count full-weight for their chosen candidate. Once that candidate is elected or eliminated, a vote is divided equally among all non-disapproved, non-eliminated members of the top party remaining on that ballot with any such members.
  • Undelegated votes are divided equally among all approved, non-eliminated candidates on that ballot.
  • Any candidates who reach the quota are immediately and simultaneously elected, and their ballots are reweighted to eliminate a Droop quota.
  • If there are no candidates who reach the quota, the party with the fewest votes is identified, and the candidate from that party with the fewest votes is eliminated. All votes for that candidate are reassigned as outlined above.
  • If the above finishes without electing a full slate:
  • All ballots are reweighted to 1
  • All elected representatives return to being hopeful candidates
  • the Droop quota is decreased as if there were one more seat (that is, it first changes from (V+1)/(S+1), to (V+1)/(S+2) )
  • The counting process is rerun from the beginning. If there is still no full slate, the quota is reduced again (to (V+1)/(S+3), etc.) and the counting repeats, until there is one.
  • Each district "drafts" one member of each elected party from the elected slate.
The draft proceeds as follows:
  • First, each representative is drafted by their home district.
  • From then on, the draft proceeds in descending order of votes. That is, if more votes from district 1 go to candidate A than any other eligible district:candidate pair, then A is drafted to that district.
  • General rule: All representatives from a party must be drafted N times before any representative from that party may be drafted N+1 times.
  • General rule: No district may draft two representatives from the same party.
  • Your representative is the member of the party you voted for who is representing your district. If no member of the party you voted for was elected, then you may look at the public ballot of your chosen candidate to see which of your district's representatives is yours.

Sample Ballot

District 5 ballot
Vote for one candidate to delegate your vote, or otherwise vote for as many candidates as you approve:
John Adams (Yellow Party, district 5) (Prefers Yellow Party except for Zapatero)
Michelle Bachelet (Silver Party, district 5) (Prefers Silver Party, then Purple Party)
Winston Churchill (Purple Party, district 5) (Prefers Purple Party, then Silver Party except for Yarrow)
▢ Alfred Deakin (Yellow Party, district 6) (Prefers Yellow Party then Silver party except for Yarrow)
▢ John Edwards (Silver Party, district 6) (Prefers Silver Party then Purple party)
Vicente Fox (Orange Party, district 6) (Prefers Orange Party then Silver party)
▢ Inder Gujral (Yellow Party, district 4) (Prefers Yellow Party)
▢ Stephen Harper (Silver Party, district 4) (Prefers Silver Party)

▢ ________________________(write-in)
▢ ________________________(write-in)

If you only vote for one candidate who does not win, your vote may help elect that candidate's preferences, unless you check the box below:
▢ Do not delegate.

Note: When you vote for just one candidate, you are delegating your vote to him or her. This allows your vote to help elect a similar candidate if your favorite cannot win. Your vote will never go to a candidate who is not in your favorite's declared preferences listed above.

If you vote for more than one candidate, or if you vote for a candidate with no declared preferences, your vote is not delegated. In that case, it does not matter whether you check the "do not delegate" box above.

Example

Tennessee's four cities are spread throughout the state
Tennessee's four cities are spread throughout the state

magine that Tennessee is having an election on where to locate 3 public universities. The population of Tennessee is concentrated around its four major cities, which are spread throughout the state. For this example, suppose that the entire electorate lives in these four cities, and that everyone wants to live as near as many universities as possible.

The candidate sites for the university are:

, the state's largest city, with 42% of the voters, but located far from the other cities

  • Site 1
  • Site 2

, with 26% of the voters, near the center of Tennessee

  • The "Eastern Party", composed of:

, with 17% of the voters

, with 15% of the voters

The preferences of the voters would be divided like this:

42% of voters
(close to Memphis)
26% of voters
(close to Nashville)
15% of voters
(close to Chattanooga)
17% of voters
(close to Knoxville)
  1. Memphis 1
  2. Rest of Memphis party:
  • Memphis 2
  1. Nashville
  2. Eastern party
  • Chattanooga
  • (Knoxville not approved)
  1. Nashville
  2. Eastern party:
  • Chattanooga
  • Knoxville
  1. Memphis party
  1. Chattanooga
  2. Rest of Eastern Party:
  • Knoxville
  1. Nashville
  2. Memphis party
  1. Knoxville
  2. Rest of Eastern Party:
  • Chattanooga
  1. Nashville
  2. Memphis party


The quota is 25%. Since both Memphis (site 1) and Nashville are over the quota, both are elected first. Memphis votes are multiplied by 17/42 and transferred to Memphis site 2, and Nashville votes are multiplied by 1/26 and then split evenly between Chatanooga and Knoxville. Totals are now:

  • (Memphis 1: 25% (elected))
  • Memphis 2: 17%
  • (Nashville: 25% (elected))
  • Chatanooga: 15.5%
  • Knoxville: 17.5%

The party with the fewest remaining votes is the Memphis party. Within that party, Memphis 2 is the site with the fewest votes (in fact, the only remaining site), so even though it has more votes than Chatanooga, Memphis 2 is eliminated. The votes are pass over the already-elected Nashville to tranfer to the Eastern party. Within that party, Memphis disapproved Knoxville, so the full total is transferred to Chatanooga. Chatanooga now has 32.5%, more than the 25% quota, so it is the third and final site.

If Knoxville had not joined a party with Chatanooga, then Chatanooga would have been eliminated, and Knoxville would have been the final site. But Chatanooga could have responded by threatening to prefer a second Nashville site, or even Memphis 2, over Knoxville, if Knoxville would not cooperate in the Eastern party. In the end, Knoxville's strategy may or may not have worked. In general, such strategic gamesmanship would be less profitable and more dangerous in a real election, with more seats overall as well as a significant degree of polling uncertainty.

Advantages

P

  • Proportional
  • Thus, a large majority of voters have real representation
  • Each representative is elected with the same number of votes.
  • Prudent; not a radical change from single-member districts
  • No redistricting necessary
  • If:
  • all votes are for one of the two main-party candidates in the voter's district,
  • all candidates approve everyone from their party
  • and the districts are divided fairly so that plurality would give a proportional result
... then PAL representation (like Balinski's "Fair Representation") gives the same results as plurality. These assumptions will not generally be perfectly true, but they will generally be close to true, so PAL representation will give results that are recognizably similar to those of single-member districts. It is hoped that this would make it a more acceptable system to politicians who have won under single-winner rules.

A

  • Accountable
  • Voters, not party bureaucrats, decide which members of a given party get seated.
  • Since the total votes needed for election is higher, the "margin of victory" is reduced. There are no safe, gerrymandered seats where corrupt representatives can hide.

L

  • Local
  • Representatives know who is a constituent and voters know who is their representative.
  • Neighbors can organize to lobby their shared representatives.
  • Fair attention for local issues.

Justification

PAL representation is inspired by Michel Balinski's "Fair Representation" and by SODA voting. From the former, which is used for municipal elections in Belgium, it inherits the combination of geographical districts and proportionality. However, unlike Fair Representation, each candidate elected by PAL representation has received (directly or indirectly) the same number of votes. From SODA voting, PAL representation inherits the simple, spoilproof ballot format and the optional vote delegation.

A modified version of STV is used as the proportional system for simplicity. Other proportional systems (such as BTV [Bucklin Transferrable Vote]) would also work. The equal ranking, and resulting fractional division of votes, is necessary for three reasons. First, it allows for approval-style votes to be counted without complicating the ballot. Second, it allows candidates to exercise judgment independently from their party (disapproving of certain party members), but keeps the voter's judgment as primary. If candidates couldn't exercise judgment, parties would have to waste energy keeping out "crazy" candidates who affiliate only because of the transfer votes they might get. If candidates could fully-rank within the party, as would happen if the PR system were standard STV, there would be too many opportunities for logrolling, at a level of detail where voters wouldn't realistically keep track or hold candidates accountable. Third, equal-ranking allows us to claim that this system could, under reasonable circumstances, elect exactly the same representatives as a non-gerrymandered single-member-district system.