STV & the Labour Party

STV & the Labour Party

There’s a sudden revival of interest in STV as the LP adopts it as a means of electing the CLP reps. There are in my mind, three problems with STV for party managers and one for voters. The fact that “order” can be critical in the results is important. When combined with the degree of discipline within Party voting blocs and the propensity to bleed votes from the block, getting the quota early is of advantage to parties. The problem of avoiding having large numbers of your votes trapped in the losing quota is also critically important for party managers particularly if the quota is high.

The Order based nature of STV counting leads to a series of well-known problems with STV in that it is one of the easier systems to game and has a number of design features which encourage manipulative or gaming behaviour. STV is not monotone, participative, consistent nor does it meet the No-Betrayer criteria.

There is no strategy that can compensate for a bloc’s voters not voting for all the candidates in the slate. Even within the activist or membership layer, many are more committed to their faction than to the Party, which may lead people to desert their first choice slate for another as the individual candidates become distasteful to the voter. I am curious if we could model the effect this ‘bleed’. The speed of desertion may well be determined by the slate construction as some on the slate might be exceptionally unacceptable to the otherwise loyal electorate. We should also note that not transferring reduces the quota[1] and so is equivalent to a (part) vote for all remaining candidates and acts as de-facto vote in favour of the highest remaining contender.

Early success militates against having votes lost in the losing quota, particularly as the STV transfers surpluses before eliminating candidates.

If running a complete slate, the offer of a recommendation to support as a second choice is not worth so much.

The disadvantage to voters is that their optimal strategy may not involve voting in a straightforward way as it may be best if someone likely to pick up a lot of transfers is eliminated before the transfers occur. This is more acute in instant run-off elections and depends on whether they want a candidate to win or prefer that others lose.

I can’t see what to do about weak discipline. If we take the example of the UK where we have Labour, the Greens, the Lib Dems and the Tories, we can see how people, who’s first choice might be, say, Labour might switch to the Green list after one or two votes for what ever reason and the Greens might go in both directions to Labour or to the LibDems. The system is designed to have this effect.


[1] This is the failure to meet the Participation Effect. …

Voting Systems Theory and STV

Voting Systems Theory and STV

It is important to understand that a bunch of clever people have thought hard about voting systems; we don’t have to invent this. I remember that our management in Sun Professional Services tried to imbue us with the mantra, “Innovate, Don’t Reinvent” and others have declared that the process of innovation is standing on the shoulders of giants. Voting system qualities known as criteria have been defined. There may be some as yet undiscovered criteria, but it would be best if we debate the pro’s and con’s using an agreed categorisation and science.

One has to be brilliant to be both in a minority and right, and most of us are not that brilliant.

Wikipedia, on their article, Comparison of Electoral Systems, says this,

Attitudes towards systems are highly influenced by the systems’ impact on groups that one supports or opposes, which can make the objective comparison of electoral systems difficult. … To compare methods fairly and independently of political ideologies, voting theorists use voting method criteria, which define potentially desirable properties of voting methods mathematically.

Wikipedia – Comparison of Electoral Systems

One thing we should note is that not all criteria can be applied to all systems, the key differences are between single winner systems, and multiple winner systems and then between list based and non-list based systems.

While some consider and seek to judge instant run off elections, sometimes referred to as the Alternate Vote as a special case of STV i.e. an STV with only one winner, the fact that there is only one winner makes it a separate and quite different system. This is shown by the fact that it passes and fails different voting criteria. Also, in AV elections, there is no transfer of a surplus votes and the minority i.e. the wasted voted can be as high as 50% – 1. This is better than simple plurality systems where the losing proportion can easily be quite high majorities. It seems to me that one critical goal of democratic voting systems should be to ensure that the “wasted” or losing votes are as small as possible.

Some criteria only apply to singe winner elections, and while it’s hard to game an STV election, it is not impossible. Games can be played by candidate/parties or by voters. STV’s problems come from the fact that surpluses and eliminations occur in an order and thus transfers are impacted by this ordering.

The Wikipedia article tests STV against 7 voting systems criteria and fails it on five. Some of the criteria seem to be remarkably similar and, it seems to me, all relate to honesty and motivation in voting behaviour and how the voting system reflects this honesty. STV fails the Monotonicity Criterion as there are cases where you can support your preferred candidate by down ranking them. It fails the Consistency criterion, probably by design and I am not sure it’s all that desirable, but this is about sub-set aggregation which can’t be done in STV. It also fails the Participation criterioan, that your voice is always stronger if you vote, and “No favourite betrayal”, where you have no incentive to vote for anyone other than your favourite.

It’s certainly not perfect but we should learn from thinkers that have gone before us.  …

e-voting: transparency and secrecy

e-voting: transparency and secrecy

I have just had a another do-over on the subject of e-voting. It is my view that,

It is not possible to build a single system that offers both a transparency of result and secrecy of the ballot.

Some people argue that our current system fails these tests but this is not so. The UK’s current process involve three systems, one to check that the voter is entitled, one to record the vote, and one that records the intersection between the other two for the purposes of audit. The ballots and their intersections are not indexed. While the systems are designed to be tracked, doing so requires massive privilege and is very expensive. N.B. Expense is an IT security defence. …

There’s a reason that votes are secret

I didn’t win again, but in another part of the business a comrade asked for a motion to be voted on via secret ballot. This is what the rules say

C15.I.2.M.ii   Ballot votes shall be held at meetings to select candidates and where otherwise provided for in the Party constitution; and where requested by any member supported by at least two others.

The Chair was advised that the request for a secret ballot required the agreement of the meeting, I have looked and can’t find such a rule. The purpose of this rule is to avoid intimidation and coercion. I did ask where this was defined, but got no answer.

We have now set a precedent that secret ballots can only be agreed by the whole meeting. It’s a charter for bullies. …

Balancing interests

I have been thinking about secure election systems for a while. Two events have provoked me to consider this issue today. Firstly, I was looking at building a voting system in WordPress and came across YOP Poll which does not have a secret ballot hidden from the system administrators. Secondly, the Lewisham Momentum meeting tonight it seems is going to have Momentum staff or nominees on the door.

The point of principle is that when building trustworthy systems, they must have a segregation of duties and are best observed by competing interested parties who can call foul if something wrong is happening.

In the examples above, neither the software, nor its administrators should be trusted, and in the second example, since there is no audit of their decisions neither should the door keepers who are accountable to no-one. …

Fair Votes

Fair Votes

The Electoral Reform Society (ERS) has produced a report on the general election. It’s subtitled, “Volatile Voting, random results.”  First Past the Post (FPTP) claims to be designed to deliver Governmental stability, but in the last three elections, it has failed to do this twice. Furthermore it exaggerates local & regional differences, e.g. Scotland, Wales and the SE, where the leading parties margin of victory in terms of seats is higher than it’s vote warrants and the losers are under-represented. In this article, I have summarised what I see as the main themes and illustrated what ERS believe to be the impact of implementing a fairer voting system. I also make the point that different systems will cause different behaviour and I finish with a look at Germany’s PR system and a call for smaller constituencies in the belief that it will lead to a better relationship between MPs and their electors. …

Swing!

YouGov have looked at where the Party’s votes came from compared to 2015 and produced a Sankey Diagram, which I think is really cool.

I am not sure it shows the first time voters; there should be a black segment on the left with the label “Didn’t Vote”. The original has overlays showing the swing from Tories to Labour and the loss of votes by the small parties. Labour’s challenge was to win votes from everywhere including those that didn’t vote. It actually did this, although not enough to win the election; those who thought it was too much for one election were right. …