PRSTV - Our voting system explained

Part 2: The Count

To show how the voting process outlined in my previous post feeds into the counting process I’m going to work through an example of an election from the first count all the way to the final count.
This post will include the detail that I omitted from my original post.

So the example is the Cork South-Central election from 2011. At this time the constituency was a 5-seater and the Quota was set at 10,674 votes. This figure is calculated by dividing the total number of valid votes by the number of seats +1 and adding 1 to the result. So (64040/(5 + 1)) + 1 = 10,674

Here's how the counts went:




Count 1
After counting all of the #1 preferences for each of the 17 candidates they ranged from 10,715 votes for Micheal Martin all the way down to 90 for Gerard Linehan . Since Micheal Martin exceeded the quota he was deemed elected and his surplus of 41 needed to then be transferred to other candidates. At this stage all of Martin’s votes are checked and sorted into different parcels based on who the #2 preference was. Any ballots that only had #1 preferences for Micheal Martin and nothing else are deemed Non-Transferrable and set aside. Given that there are 16 candidates remaining that means that there could be as many as 16 different parcels. The surplus of 41 votes is now divided between the remaining 16 candidates in proportion to how large each of the parcels are. This resulted in:

• Michael McGrath: +27 (It makes sense that McGrath gets the bulk of these as he’s Martin’s FF running-mate)
• Ciaran Lynch: +3
• Simon Coveney: +3
• Jerry Buttimer: +2
• Deirdre Clune: +2
• Chris O’ Leary: +1
• Paula Desmond: +1
• Mick Finn: +1
• Dan Boyle: +1

The actual ballots that are physically transferred in each case are taken from the top of each parcel. It should be noted that prior to counting, the ballots are randomised by mixing them up in a large box (about the size of a bath-tub). This adds a degree of randomness to ensure that all of the transferred ballots don’t originate from the same ballot boxes (which might favour one candidate or another for geographical reasons).

Count 2
After Martin’s surplus 41 votes are transferred to the other candidates nobody has exceeded the quota. At this stage what typically happens is the bottom placed candidate is eliminated and their votes are transferred. However an interesting scenario now occurs. The bottom 3 candidates (Linehan, O’Driscoll and Isherwood) combined vote count of 375 is still less than the 4th last candidate’s (Dunphy) current total of 448. This means that if they were eliminated one at a time and even if they transferred all of their votes to each other they wouldn’t be able to bridge the gap to Dunphy. In this scenario, in order to save time all 3 bottom candidates were eliminated and each of their ballots are transferred to their highest remaining (ie not Martin) preference. 14 of these were Non-Transferrable and the remaining 361 were transferred as follows:

• Mick Finn: +53
• Chris O’ Leary: +40
• David McCarthy: +37
• Sean Dunphy: +33
• Ciaran Lynch: +32
• Michael McGrath: +26
• Ted Neville: +24
• Paula Desmond: +23
• Diarmaid Ó Cadhla: +23
• Simon Coveney: +21
• Jerry Buttimer: +20
• Deirdre Clune: +20
• Dan Boyle: +9

Count 3
Nobody exceeds the quota. Dunphy remains in last place. He alone is eliminated and his 481 votes are transferred. Note that this includes the 33 votes that were transferred to him from the bottom 3 candidates in the previous count.

I’ll skip ahead now as the process doesn’t really change much for the next few counts…just the bottom candidate/candidates being eliminated and their votes being transferred.

Count 9
After the 8th count Labour’s Paula Desmond was eliminated and as expected the majority of her 4,127 votes transferred to her running mate Ciaran Lynch who received 2,644 of her transfers. Significantly this was enough to put him over the quota and he became the second candidate to get elected.
He now had a surplus of 1,891 ballots to be transferred. It’s important to note that these do not come from his original votes. They come from the batch of votes that were transferred to him from Paula Desmond. They way they do it is they examine the 2,644 votes and place them into different parcels for each of the remaining candidates. The 1,891 votes to be transferred are then transferred to the remaining candidates in proportion to the size of those parcels. This resulted in transfers of:

• Chris O’ Leary: +549
• Jerry Buttimer: +378
• Simon Coveney: +341
• Deirdre Clune: +326
• Michael McGrath: +273

Note: Those transfers don’t actually add up to 1,891 presumably because there wasn’t actually 1,891 transferable votes in the 2,644 parcel received from Desmond

Count 10
Lynch’s transfers put Coveney over the quota thereby giving him the third seat. His subsequent surplus of 198 votes isn’t enough to bridge the gap between Deirdre Clune and Chris O’ Leary in last place and so Clune is also eliminated at this time

Count 11
Not surprisingly the transfers from FG candidates Coveney and Clune disproportionately go to the remaining FG candidate Buttimer and he exceeds the quota and becomes the 4th candidate to be elected

Count 12
Buttimer’s surplus is distributed between the remaining 2 candidates. After this Chris O’Leary is eliminated and Michael McGrath takes the final seat without reaching the quota.