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Monday, March 19, 2018

CSM 13 Election: Explaining The Single Transferable Vote

Starting with the election of the 8th Council of Stellar Management, CCP has used a modified version of the Wright single transferable vote system (STV) to conduct all elections. Before 2013, CSM elections were conducted using widely used First Past the Post (FPTP) system. Players would cast votes for a single candidate per account, with the 14 candidates receiving the most votes becoming either members of the CSM going to the summits in Reykjavik or serving as alternates. A simple to understand way of conducting an election.

The design of the single transferable vote system aims to elect candidates who are more representative of the players who vote in the election. For some background about STV, I'll turn to UK-Engage, a company that provides voting services to both public and private organizations:
"The Single Transferable Vote (STV) is a form of proportional representation voting system which uses preferential voting, usually in multi-member constituencies. Candidates don’t need a majority of votes to be elected; all they require is a known ‘quota’, or share of the votes, determined by dividing the number of valid votes cast by the number of positions to be filled, plus one..."

"Under STV, an elector has a single vote that is expressed by ranking the candidates in preference from ‘1’ until the elector cannot choose between the remaining candidates. As the count proceeds and candidates are either elected or eliminated, this vote can be transferred to other candidates according to the voter’s stated preferences. In a Single Transferable Voting system very few votes are wasted; unlike other voting systems, particularly First Past the Post, where the votes of all but the winning candidate are wasted."

"STV is arguably a much more representative and inclusive voting system as it gives voters more choice than any other system. This choice puts more power in the hands of voters, rather than the political parties: under other voting systems political parties can more easily determine who is elected. Under STV some would say that an elected representative is much more accountable to the electorate than to their party superiors."
UK-Engage also listed several advantages and disadvantages to the single transferable vote system. Distilling the lists down to those that apply to EVE, they are:

Advantages
  • Under STV fewer votes are ‘wasted’ In other words, losing candidates receive fewer votes and run-away winners receive only the votes needed for victory. This means that most voters can identify a representative that they personally helped to elect
  • When voters can rank candidates, the most disliked candidate cannot win, as they are unlikely to pick up second, third and lower-preference votes.
  • By encouraging candidates to seek first, as well as lower-preference votes, STV removes the need for tactical voting. Tactical voting is when a voter supports another candidate more strongly than their sincere preference to prevent an undesirable outcome.

Disadvantages
  • A system allowing voters to rank candidates is prone to behavior termed ‘donkey voting’, where voters vote for candidates in the order they appear on the ballot. CCP fights against donkey voting by randomizing the candidate list for each vote.
Explaining how the Wright STV system works is a little challenging. Instead of confusing the issue, I will post an explanation from Wikipedia, followed by an example based on a CSM election. First, the explanation:

"The system uses the optional Droop quota (the integer value of the total number of votes divided by one more than the number of vacant positions plus one) and the Gregory method of weighted surplus transfer value of the vote in calculating a candidate's surplus transfer value which is then multiplied by the value of each vote received by the candidates whose votes are to be redistributed, as is the case in the Western Australian upper-house elections.

"Unlike the Western Australian upper-house electoral system, the Wright System uses a reiterative counting process that differs from the Meek's method as an alternative to the method of segmentation and distribution of excluded candidates' votes.

"On every exclusion of a candidate from the count the counting of the ballot is reset and all valid votes are redistributed to candidates remaining in the count initially at full value.

"In each iteration of the count, votes are first distributed according to the voter's first available preference, with each vote assigned a value of one and the total number of votes tabulated for each candidate and the quota calculated on the value of the total number of valid votes using the Droop quota method.

"Any candidate that has a total value equal or greater than the quota is provisionally declared elected and their surplus value distributed according to the voter's nominated subsequent preference. If the number of vacancies are filled on the first distribution the results of the election are declared with all provisionally declared candidates being declared the winner of the election.

"If the number of candidates provisionally declared elected is less than the number of vacancies and all candidates' surplus votes have been distributed then the candidate with the lowest value of votes is excluded from the count. The ballot is reset and the process of redistribution restarted with ballot papers being redistributed again according to the voters next available preference allocated to any continuing candidate. This process repeats itself until all vacancies are filled in a single count without the need for any further exclusions.

"The Wright System takes into account optional preferential voting in that any votes that do not express a valid preference for a continuing candidate are set aside without-value and the quota is recalculated on each iteration of the count following the distribution of the first available preference. Votes that exhaust as a result of a candidate's surplus transfer are set aside with the value associated with the transfer in which they exhausted."
Confused? I was when CCP first announced the use of STV in 2013, the dev blog instructed players to visit Wikipedia for an explanation. I needed an example before I truly understood how the algorithm worked. Having covered five CSM elections using the STV, I think I can do a little better than the generic mechanical explanation. In the below example, I will not only go through the mechanics, but introduce some of the situations that occur in a CSM election.

Example Election

In our example election, 8 candidates are vying for 4 seats. We can divide the candidates into 3 security zones, each with their own political dynamics.

Null security space: In our mythical election, we have three null sec voting blocs. They are:

Goonswarm Federation (GSF) - Goonswarm historically is the electoral powerhouse in CSM elections. In our example, GSF is running two candidates, Aryth and Innominate, winners in both the CSM 11 and CSM 12 elections. The Goon campaign team usually supports other null sec entities, so will finish off their voting slate by supporting candidates from fellow Imperium member The Bastion as well as Brave Collective.

The Bastion - Smaller alliances within the Imperium often attempt to win a seat on the CSM. In our example, The Bastion's Sullen Decimus, a member of CSM 11, will try to win a third seat for the Imperium. The Bastion made a deal with Brave Collective to put his name second on their ballot if The Bastion would do the same for Brave's candidate.

Brave Collective - Brave always seems to win whenever they officially back a candidate in a CSM election. In our example, Brave will run CSM 12 member Yukiko Kami. Brave's voting slate will mirror The Bastion's, except for putting Yukiko in the top slot and moving Sullen down to the second spot.

Wormhole space: The dynamic in wormhole space is a little different than in null sec. Instead of working within established major blocs, wormholers got together and two candidates, Noobman and ExookiZ, rose to the top. The backers of each candidate promised to put the other faction's candidate in the number two slot to ensure at least one wormhole candidate would win. Wormholers didn't care about candidates from k-space, but didn't want to waste the other two slots, so filled them in with Sullen Decimus and Yukiko Kami.

High security space: High sec is a very splintered, unorganized area of EVE. In our mythical election, two candidates representing two very different playstyles will run. They are:

High sec gankers: The high sec ganking community is very loud, very passionate, but very small. To maximize turnout, the famous ganker James315 is running in our election. Since Goonswarm's Ministry of Love often operates with the gankers in high sec, James315 fills the remaining three slots on the ballot with members of the Imperium.

High sec carebears: To say that high sec miners, mission runners, and haulers do not like high sec gankers is an understatement. But the residents of high sec, with the exception of the gankers, are a pretty apathetic lot. The turnout from those who enjoy PvE in high sec is usually very low. Additionally, in our example, they could only come up with two other candidates to vote for: Sullen because he did some mining stuff on CSM 11 and ExookiZ due to giving some presentations at Fanfest.

The Vote

Initial Vote
In our election, 1800 players voted. To calculate the number of votes required to guarantee election, known as the Droop quota, we use the following formula:

(Number of votes cast / number of positions + 1) + 1

The initial quota is 361. The number of votes for each candidate at the beginning of the round is below.

From the audit file

Innominate starts the round in last, but that won't last long. Aryth has 650 votes, which exceeds the quota. Aryth wins the first seat and the extra 289 votes he didn't need fall to the second candidate on the Goonswarm ballot, Innominate. At the end of the round, the tally is:

From the audit file

Since the voting does not have 4 winners, the algorithm removes the candidate with the lowest vote total, Sullen Decimus, and distributes his votes to the number two candidate on The Bastion ballot, Yukiko Kami.

Round 2

Round 2
The number of ballots is still 1800, which means the quota is still 361. The tally for each candidate at the beginning of round 2 is:

Beginning of round 2, from the audit log

Not much happens in the round. Once again, Innominate receives the overflow vote from Aryth to stay in contention for a seat.

End of round 2, from the audit log
Since the voting does not have 4 winners, the candidate with the lowest vote total, ExookiZ, is eliminated and his votes distributed to the number two candidate on the Wormhole #2 ballot, Noobman.

Round 3

Round 3
The number of ballots is still 1800, which means the quota stays at 361. The tally for each candidate at the beginning of round 3 is:

Beginning of round 3, from the audit file
The cooperation between the wormhole candidates worked, with Noobman exceeding the quota in round 3 of the voting simulation. Innominate, as was the case in the first two rounds, receives 289 extra votes from Aryth. With Noobman meeting quota and winning a seat, his 39 excess votes go to Yukiko, allowing him to surpass Lorelei's total. The tally at the end of the round is:

End of round 3, from the audit file
Round 4

Round 4
With the elimination of Lorelei Ierendi in round 3, the high sec carebear voting slate expires, reducing the number of ballots from 1800 down to 1570 votes. The result is a decrease in the quota from 361 down to 315.

Beginning of round 4, from the audit file
The reduction of the quota increases the trickle-down from the candidates who already exceeded the quota. So instead of Innominate receiving 289 of Aryth's excess votes, he receives 335 votes. Yukiko receives more votes from Noobman, increasing his total from 39 to 85 votes. Due to the decreased quota, Innominate exceeds the quota by 20, winning the third seat and passing those votes to Yukiko as well.

The final round, from the audit file
I'm not exactly sure why the algorithm indicates Yukiko had only 314 votes while the actions during the round show Yukiko should have 315 votes. Either way, Yukiko surpasses James315's vote total of 310 and wins the final seat.

(UPDATE: 1 April 2019: Through taking Python classes, I've learned that Python sometimes handles numbers a little wonky, resulting in slight discrepancies like the one mentioned above.)

Conclusion

Perhaps a game as famous for its complexity as EVE Online should use a complex voting system like the modified Wright single transferable vote for determining the winners of the Council of Stellar Management election. Others may argue that using a single transferable voting system adds needless complexity to an election that historically has low voter turnout. I just wish I didn't need to write a 2100 word essay in order to explain how the voting system works.

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