The "STV for Canada" website provides a model of the outcome for federal election if STV was brought in in Vancouver island and Toronto. But the group's expectation of STV's performance varies from mine. And its mathematical analysis is somewhat weak, to my way of thinking.
Just a little on the Toronto test case - It is envisioned to divide part of Toronto into three 4-member districts. This seems to be too few members in a district. Acceptable if no choice but not good enough if a city is large enough to do more and Toronto is. 12 seats would be better divided into twp districts, one with seven seats and the other with five seats, I think.
The Toronto test case is difficult to judge because the Toront test case concerns 12 ridings in central Toronto but Central Toronto is often thought to contain 11 ridings. And as the "STV for Canada" website does not give the names of the ridings it considers Central Toronto it is not clear which ridings they are using for the test case.
For sure Toronto has 25 ridings so it is too bad that those 25 ridings were not used to prove the case for STV - a system I firmly believe can work anywhere. By the way, if we are talking about STV covering all of Toronto, I would suggest three districts, two with 9 seats and one with seven seats, or five districts, each with five seats.
The Vancouver Island test case is more clear.
The Vancouver island model sees the island made into two multi-member districts, changing it from its present 7 single-member districts.
The three existing northern ridings would be grouped together to create a three- member riding;
the four south Island ridings would be grouped together to make a four-member riding.
This is okay but a larger District Magnitude would allow more proportional representation. That is to say, a riding covering the whole island would be preferable.
If local representation would be thought threatened by this, remember that if local representation was an important desire for voters, if one-eighth of the voters anywhere - an eighth being quota - voted just for the local candidates, political stripes apart, they would have one. And there would be nothing the other seven-eighths of the voters could do about it.
But taking the three-member district and the for-member district as given, and making the same assumption that the "STV For Canada" website makes, that people in the hypothetical STV election would cast their votes for the same candidates as they did in 2015 under FPTP,
I did some mathematical analysis - and arrived at different conclusions.
"STV for Canada" says that in the three-member riding an NDP, a Liberal and a Conservative would be elected.
This result is the same as giving one seat to each of the three leading parties.
And in the four-member riding in the south, "STV for Canada" predicts that a seat would be won by the NDP, the Liberals, the Conservative and the Green.
Again this result is the same as giving one seat to each of the leading parties, four in this case.
It could happen that way but to be proportional the party vote tallies would all have be near the quota to produce this result. STV does provide roughly proportional representation at the district level so it is natural to expect that to produce such an equal representation each party must have had about the same number of votes.
However, basic compilation and addition tells me this:
North
three old ridings Courtney Nanaimo and North
NDP 75,000 votes
Conservatives 53,000
Liberal 47,000
Green 27,000
The Greens in the North are the only ones who would not have their candidate be elected in the "STV for Canada" results. Other than a handful of also-rans whose votes totals rarely went over 3 digits.
"STV for Canada" says that that 27,000 voters in the north area of the Island are the only ones not represented. These are the 6 percent of island voters said not to be represented.
That's true enough but 27,000 votes in the 172,000 of the north riding would be 16 percent of the voters in the district.
And we see that giving one seat to each of the three most popular parties is not proportional. For example, the NDP receives the same number of seats as the Liberals although the Liberals have less than two-thirds of the NDP count.
but the STV for Canada website states:
"Single Transferable Vote (PR-STV) is the original British proportional system. The aim of proportional representation is to produce a legislative body where the voters are represented in proportion to how they voted."
According to the website, Craig Henschel, BC Citizens Assembly, put it this way: "STV means that each MP is elected by almost the same number of voters, the benefits of multi-member districts and voter choice."
But in the expected 1/1/1/0 result, the three MPs would be elected by a very different number of votes.
Quota in the hypothetical STV election would be 43,000 (total 172,000 divided by four).
Each 43,000 votes will take one seat.
Only 43,000 NDP votes would be all that would be needed to take the party's first seat. Leaving 32,000 NDP votes not used.
The 32,000 NDP un-used NDP votes and the 27,000 un-used Green votes are half again more than a full quota.
The surplus NDP votes alone amounted to only 11,000 fewer votes than quota.
Recall that the "T" in STV means transferable and that vote transfers are an important part of STV. It is likely that at least 11,000 of the 27,000 votes freed for transfer by the elimination of the Green candidates would go to the NDP, giving that party's candidates 43,000 votes and enough for an additional seat and likely depriving the Liberal of its one.
The Liberals did receive 47,000 votes, enough for one quota, but this is not as many as the number of second-seat NDP votes and transferred Green votes, if at least 15,000 of the 27,000 Green votes go to the NDP.
The scant three members make the result fairly unknowable in advance. There would not be smooth proportionality, no matter what the result.
But the result under STV could safely be assumed to be
NDP two seats, Conservative one seat, Liberal and Greens zero
as likely as the 1/1/1/0 result predicted on the website.
(Of course there would be considerable leakage during the course of the vote transfers. When votes are transferred, each of the surviving candidates usually receive at least some, but as this leakage hits all transfers, the relative strength of the parties is generally maintained excepting elections and eliminations.
By the end of the vote counting under STV, many votes would prove to be exhausted, having no remaining un-used back-up preferences. These contribute to the small percentage of votes declared wasted under STV.
So it would be unfair to pretend to predict the certain result of the Vancouver Island STV elections. Voters have influence on the result in a way that is not provided by FPTP, but at the same time vote splitting and small shifts in voting behaviour does not make the vast differences that they produce under FPTP.
It can reliably be expected that STV will produce mixed roughly proportional party representation in every district, if the prediction of which specific candidates elected is difficult. This is also true because the new multi-district would see voters able to vote for any of the candidates instead of being confined to the candidates in only one-third of the area as previous under FPTP. )
Predicted 1 NDP/1 LIberal/1 Conservative/0 Green results not proportional
It seems that the "STV for Canada" website assumes that representation is taken to be the fact that a candidate of your party is elected in your district. If that is so, we don't need STV at all, but instead a system where each voter casts one vote and the most popular candidate of each party, to the number of the seats to be filled, is declared elected. But that is not proportional - and it is not STV.
STV would not necessarily give one seat to each major party in each district. But if not would the number of wasted votes increase?
If the NDP takes two seats and the Conservatives take one, how many votes would then be unrepresented in the new North riding?
First, let's see how many of the votes would be used to elect a candidate when two NDP and one Conservative is elected.
75,000 NDP voters
11,000 Greens for sure (Probably many more of the 27,000 would go to the NDP as well but there they would be found to be surplus and probably eventually moved to the exhausted pile.)
43,000 Conservative (10,000 of the party's 53,000 votes being surplus)
thus 129,000 out of 172,000 total votes.
Thus minimum of 75 percent would have been used - the amount of three quota.
In the vote transfers, many votes would have gone to the first two candidates who had already been elected so they would have been put on the exhausted pile but those voters would have had the satisfaction of having their choice elected even if their vote did not help that come about.
So the percentage of "representation" is murkier than the 94 percent said to be created by the "STV for Canada"'s 1/1/1/0 result but I expect the 2/1/0/0 result would be more proportional and more in line with the expectation of the performance of STV in practice.
The performance of STV as to the number of wasted votes - the number that were not used to elect a candidate - is always about one quota less than 100 percent. With three seats it would be about a quarter wasted. Any extra votes a candidate picks up over and above quota are transferred away.
With 5 to be elected it would be about 17 percent wasted.
But of course the exhausted pile is full of votes that were not needed to elect the candidate marked as preferred. These were not used so were technically wasted but the voters should be happy about the outcome -- his or her choice was elected.
But even if we throw the "satisfied" votes in the exhausted pile and list them as wasted, still we should note that the one quarter of votes wasted in the hypothetical North Vancouver Island riding compares well to the 40 to 60 percent or more wasted under FPTP.
In the south we find the same loose interpretation of the result under STV.
In Cowichan, Esquimalt, Saanich and Victoria, the old ridings now grouped together in a four-member riding, the NDP and the Greens each receive about a third of the 270,000 votes, leaving only about a third of the votes to the Conservatives and Liberals together. Why then should all four parties receive one seat each?
Instead probably it might be
two NDP and one Green, and a Liberal or Conservative for the last seat,
or
two Greens and a NDP, and a Liberal or Conservative for the last seat.
With a scant four members there is not alot of leeway or subtlety allowed in presenting the case of two parties receiving about the same amount and two others trailing.
We can expect that 20 percent of the votes (one quota) would be wasted (counting all exhausted votes as wasted). This is very good compared to the 40 to 60 percent usually wasted under FPTP.
Seven-member riding covering the whole Island,
To provide finer grade of proportional representation, we could have the whole Island voting in one multi-member 7-member riding.
Seven is a nice number of seats in a district. It was used successfully in Edmonton when that city elected its MLAs through STV in the 1950s.
Overall,
442,000 votes 7 seats
Quota 55,000 votes
Party tallies:
NDP 157,000 votes
Conservative 100,000 estimated
Liberal 100,000 estimated
Green 112,000
So a possible/likely outcome of STV in a 7-member riding covering all of the Island:
NDP 3
Green 2
Conservative 1
Liberal 1.
Thus while the NDP took six seats and Greens one seat under FPTP in 2015, under STV all four parties would have representation roughly proportional to their vote count.
Wasted votes under FPTP in 2015
Looking at the results for the Vancouver Island ridings,
the wasted votes under FPTP on Vancouver Island amounted to 64 percent of votes cast.
North: WINNERS OTHERS
Courtney 27,000 38 percent 40,000 wasted
Nanaimo 24,000 33 percent 49,000 wasted
North 24,000 40 percent 36,000 wasted
125,000 wasted
South:
Cowichan 22,000 36 percent 39,000 wasted
Esquimalt, 24,000 35 percent 45,000 wasted
Saanich Green 37,000 54 percent 32,000 wasted
Victoria 30,000 42 percent 41,000 wasted
157,000 wasted
Thus of 442,000 votes cast on the Island, 282,000 votes were wasted.
64 percent of the Island votes were wasted under FPTP in 2015.
(About 50,000 Green votes were wasted in Cowichan, Esquimalt and Victoria alone.)
(Under STV in 7-member riding, vote waste would be about 60,000 votes or 13 percent.)
Whatever the exact texture of representation that STV would produce,
compared to FPTP, it would be:
mixed -- three or four parties would be represented proportionally,
fairer -- no one party would take six of the seven Island seats.
And it would have wasted fewer votes than FPTP.
Thank you for reading.
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