Thinking about overhangs

The concept of the second choice of party vote should work regardless of overhang rules. But if the coat-tails rule is abolished, there is an increased risk of overhangs. The method chosen to handle overhangs can disrupt the proportionality of the result.

In general, overhangs arise when a party or independent candidate win electorate seats, but the St Lague system allocates them fewer seats.

There are several main ways this can happen:

  • A dominant party overhang occurs when a large and dominant party wins more seats than its party votes justify. This happens frequently in other countries, but is very unlikely in New Zealand. Conceptually this type of overhang could occur where a party is very dominant only within a small region, but such situations have not yet occurred in New Zealand.
  • A vote-splitting overhang occurs when voters vote for a candidate for one party and give their party vote to another party. This has occurred in NZ when voters have voted for Maori party electorate candidates and given their party vote to the Labour Party. This practice could theoretically be practised widely, so gaming the system and greatly distorting proportionality,
  • A threshold-driven overhang occurs only in the absence of the present coat-tails rule. It occurs when a party wins an electorate seat, but not enough votes to pass the 5% threshold.

In reality there are overlaps between these types of overhangs, so that rules are needed that work in a wide variety of circumstances.

The threshold driven overhang occurs only if the present coat-tails rule is abolished. In New Zealand there have been several situations where MPs have resigned from major parties and created their own party. This type of situation demonstrates an inconsistency between handling of elecorate and party votes. Independents can be lone voices in parliament, while parties are allowed only if they can get to six seats (5% of 120).

At present when an overhang occurs the party or candidate is allocated a seat over and above the normal 120 seats in parliament, and the proportionality of parliament is disturbed.

Another method of handling overhangs is to take the overhang seats from the seats otherwise allocated to list votes, so avoiding extra seats in parliament. Proportionality is disturbed, but often not greatly in NZ, as the overhang seats are taken from parties approximately in turn, and in proportion to their party votes.

This method is used in a similar electoral system in Scotland. There the overhangs are mostly of the dominant party type. As a result the overhang seats are effectively taken from other parties to give to the dominant party, so substantially disturbing proportionality.

The use of a second choice of party vote does not alter the overhang problems outlined above. Dominant party overhangs are unlikely in NZ and not serious, so can be safely disregarded.

A better treatment is needed of overhangs resulting from independents without supporting party votes. It is complicated by the ideal of representation i proportional to party votes whereas an independent has not party votes.

And the solution needs to work around the inconsistency between allowing single seats for independents, but refusing representation for parties with less than 5% of the national party vote.

Here is a sugestion that could largely eliminate the overhang problem. But I need to look more closely to be sure.:

  1. in electorate contests, there will be one winner. typically in NZ with 12-20k votes.
  2. All voters who gave their electorate vote to this winner , will have their party vote redirected to that winner s party. For an independent, the party is just the candidate them selves. The winner will receive one seat from their party s allocation, irrespective of the quotient.

This method should ensures that an electorate winner receives approximately the normal quota of party votes for their seat, and uses them to gain a seat.

In this way every seat requires a quota of party votes. And there is only a limited total quantity in the election.

This system makes vote counting more complex, because it is necessary to keep a total for every combination of party vote and candidate vote.

So there are things to check here. Does this work in every likely circumstance? How would you organise vote counting?

Based on a small sample, when there are about 40 000 votes, with two major candidates, the winner gains at least about 19 000 votes. With three major candidates, the winner often received about 13 000 votes. A typicalNZ general election has 72 electorates each with 40 000 votes on average. That means 40 000 electorate votes and 40 000 party votes. This corresponds to 2.88 million votes. If a candidate wins on 13 000, there will normally be two others at about 12 000 each , and about 3 000 among other parties.

More information to come

Latest summary: Why waste 5-8% of votes?

I’m writing about the MMP threshold, to suggest that lowering it is not a solution..

The problems for small parties under MMP, arise mainly from the wasted votes (typically 5-8%) that now occur, and the consequent spoiler effects for small parties.

Voters say “I do not want to waste my vote”.  Parties say to small parties on the same side of the house “Don’t take votes from us and then waste them”.  Small parties are spoilers.  People stay away.  New parties cannot get started.

So why do we waste around 5-8% or so of votes every election?  And cause all that anguish?  There seems to be no good reason.  And lowering the threshold does not remove the problem, or the dislike of the threshold.  

Instead offer voters a second choice of party vote.  If a voter’s first choice fails to pass the threshold, their vote goes to their second choice party.  Voters will be careful to make sure either first or second choice is certain enough to pass the threshold.

Problem solved.  That 5% threshold is no longer a problem. No voter needs to waste their vote. If a party misses the thresholds, its votes will mainly go instead to a bigger party on the same side of the house.  No longer are small parties spoilers.   Wasted votes should drop below 1%.

The second choice is easy to understand, easy to implement.  One extra column on the party voting paper.  For the voter, one optional extra tick.  Vote counting is just a little more involved than at present.  Results are independent for each polling place. 

This idea solves the wasted vote problem, while not requiring any change to the threshold.  

Is this the consensus solution that solves the threshold/wasted votes problem without needing to touch the threshold percentage?

German lessons

It is commonly said that the New Zealand MMP system was modelled on the German PPR (personalized proportional representation). There may be lessons for New Zealand here. The language difference makes it more difficult to fully understand the diferences.

Here I will endeavour to explain the German system using terms familiar to those who know the New Zealand system.

My sources of information were:

The youtube video is easy to follow, but light on detail. The wikipedia page seems to use complex language, so is more difficult to follow, and uses many unfamilar terms. The Spiegel page is easier to understand but with less detail. And it is not clear just how accurate is the information provided in any of these. So this post should be read on the understanding that I have limited confidence in the details.

To improve clarity, I will refer to :

  • An assembly ( for NZ: parliament, Germany: Bundestag)
  • A mandate (for NZ: a (voting) seat in parliament, or MP, Germany: a voting seat in Bundestag)
  • Mandates can be district mandates or list mandates.
  • A district (for NZ: electorate, and <electorate MP>, Germany: district, elects a <direct mandate>, UK: constituency)

NZ and Germany both offer two votes, one for a district mandate, one for a list mandate. (German: direct mandate, <second vote>). NZ has 120 mandate assembly with 72 districts (72/120 = 60%), Germany a 598 mandate Bundestag with 299 districts (299/598 = 50%). Both systems allow overhangs to arise (a party wins more direct mandates than its party votes justify). This has happened a few times in NZ, with up to 2 additional overhang mandates. Overhangs seem more common in Germany. Germany has a complex system of <levelling mandates> to rebalance the assembly.

The German system has rules to deal with the numerous overhangs that appear there. New Zealand has had few overhangs, and so few special rules to govern them. New Zealand seems exposed to the misuse of overhangs to distort the proportionality of results

Germany has a provision that, where an independent is elected to a direct mandate, that party votes from the independent s voters are disregarded. This is to avoid those voters having double value in the election.

Both countries suffer from the problem that many voters do not understand the importance of the party vote compared with the district vote.

Germany has regional party lists, and a 5% national threshold. It is not clear how list candidates are allocated to list mandates. From which (regional) list is each mandate recipient chosen? Germany has constituent states. Regional lists seem to be lists for each state, but I am not certain

I have identified perverse effects of the 5% threshold in New Zealand, and have suggested a second choice of party vote to avoid them. I have not seen any reference to similar issues in the German system.

This page was last updated 23/10/21. Beware this post may not be accurate!

In the meantime, a two-choice NZ voting paper may look like this:

A possible two-choice voting paper layout, based on 2020 Hutt South

Beware of organised overhangs

MMP aims to allocate seats in parliament in proportional to voter support for political parties. Two-choice voting can remove most of the distortions that arise from the use of party-vote thresholds. But should an indpendent win an electorate seat, or a party win more electorate seats than its party votes justify, then an <overhang> is created. This, in the NZ system, is addressed by creating extra seats. The Maori Party has won overhang seats a few times.

But this system seems to invite manipulation, by electing independents who are not really so. A party would encourage candidates in safe seats to become independent <friends of the party>. The home party would not stand a candidate against them. These <friends> would be expected to win their electorate seats, and create an overhang.

A similar idea has already been used in Epsom, where ACT has been able to win the electorate seat, while National benefitted from the party vote. In this case, I think the move helped ACT pass the one-seat threshold for being allocated seats.

This idea might be acceptable in isolated cases, but imagine if major parties has a dozen of these arrangements each. The result could be 20-seat overhangs.

One might hope that the voters would reject such moves as unfair, and punish those practising it. Or it could become an accepted political manoeuvre.

I think that the current electoral system review should ensure that the rules make such manoeuvres more difficult. But this does not seem easily achieved.

One method would be to require, instead of votes for person and party separately, a single vote for a person and their party. Thus a vote for a Blue party candidate would also be a party vote for the Blue Party. Two-choice party voting would work well with such a system, except that the first choice would be for person and first choice party, the second for a second choice party.

See here for a Stuff article that mentions this issue.

A two-choice MMP voting paper might look like this:

A two-choice MMP voting paper might look like this

A second choice: like Supplementary vote for PR?

Supplementary vote is a voting system for selecting one person. Each voter may make a first and second choice (no more!). The top two candidates, on first choice votes, are retained. Where a voter voted for a candidate other than the top two, their second choice vote is applied, if it is for one of the top two candidates. This system is used for Mayoral races in the UK. SV is viewed as encouraging a more positive style of campaigning as candidates desire the second preferences of third parties.

Two-choice party voting has some similarities, except that it is used to measure voter support for parties under MMP. Parties passing a set threshold, on first choice votes, continue to the next stage, where they receive the second choice votes from voters whose first choice party did not pass the threshold.

Both of these systems are based on the idea that first and second choices are often clear in the voters minds. Using lower level preferences is less useful and makes complex many aspects of voting and vote counting.

These systems are simple, but get most of the benefits offfering preferences, while avoiding the complexity of multi-level preferences. Two-choice party voting means every voter can both vote for whichever party they wish, and have a say in the allocation of seats in parliament.

A two choice party voting paper might look like this (note itś simplicity!)

Keep MMP but help more votes count

There is a very simple way of solving the MMP threshold problem, and it does not require that the threshold percentage be changed or eliminated.

People dislike the threshold (at whatrever level) because it causes wasted votes And the threat of wasted votes is a big problem, and bigger than it looks. People vote less often for small parties. People don t get involved in small parties because votes for a minor party are votes taken from that party s natural coalition partners.

The 5% threshold is a big problem. Small parties have difficulty getting started. The threat of wasted votes disocurages everyone, including voters, potential small party supporters, people considering forming new parties, the bigger parties who might cooperate with potential support parties.

The threshold means that anybody voting for a minor party has a very real chance that their vote will play no part in deciding which major party will form the next government. What a way to punish new or small parties!

Making the thresholds smaller is not much of a solution. The problem is still there, smaller, but still discouraging. There seems to be a view that a proliferation of small parties in parliament is to be avoided, so abolition is not widely favoured.

Recent articles on Stuff have commented that almost no new parties have gained seats in parliament in 25 years of MMP. A large part of the reason for that is perhaps the way the threshold punishes small parties and anyone associated with them.

There is a simple solution which completely eliminates the problem of wasted votes, which retains the threshold, which helps more people have their vote count, which improves the proportionality of the system, all the while leaving the workings of MMP almost completely unchanged.

Sounds too good to be true, no? All that is needed is to give voters a second choice of party vote. If the first choice party does not make the threshold, the vote goes to the voters second choice, normally for a party the voter thinks is certain to pass the threshold.

Easy to understand. Easy to implement. Easy to vote count and report results fast. Every voter can avoid their vote being wasted. The system is more proportional. Many people supported similar ideas in the 2012 review. Does not advantage left or right. And it is still the MMP that we know and love. But without the bad part.

Below: what the modified voting paper might look like.

More details at http://onthethreshold.nz

Review of electoral law announced

The Government has announced a major review of New Zealand s electoral law. This review will include addressing the problem of the 5% party vote threshold. There is a better solution than just changing the threshold percentage.

The 5% threshold as now implemented distorts voter and party behaviour, because of the fear of wasted votes.

Everybody hates this risk of wasted votes. A vote for a small party risks being wasted and hence playing no part in selecting which party gets to lead the next government. This is of concern to voters, to small parties, and to large parties, as it makes difficulties for all of them. Just changing the level of the threshold does not solve the problem.

Two-choice party voting offers a solution that is very simple and effectively solves the wasted vote problem, while leaving MMP almost unchanged. The only change is that it gives every voter a second choice of party vote . That just requires one extra column on the party voting paper. And one extra tick from the voter, if the voter wants.

If the voters first choice party fails to pass the threshold, then that vote goes to the voters second choice party. The wise voter strategy is to make sure that either first or second choice vote goes to a party certain to pass the threshold. From then on the MMP system works exactly as now.

This very simple change revolutionalises MMP, in a way that should please everyone. Every voter can support a small party if they want, and also be sure of having a vote that counts in the allocation of seats in parliament. Big parties can cooperate better with support parties, because there need be no wasted votes. The threshold percentage can stay the same or be changed.

Here is what the modified voting paper might look like

Scottish MMP/AMS elections 6 May 2021

I am writing this late morning on 7 May 2021 in France. There was an MMP/AMS election yesterday in Scotland. And there are no results yet, it seems!

We are fortunate in New Zealand, that General Election results are processed quickly, and we seldom if ever need to go to bed on election night without having a very good idea of the result.

The Scottish system is very similar to the New Zealand one, but is called AMS, for A-additional M-member S-system. Named because they (like NZ) elect constituency MPs then ‘add’ list members to create a proportional result.

The Scottish system differs in that Scotland selects list MPs in eight regions, so that each region has it own more or less proportional result. There are no fixed thresholds, but because each region elects only about 16 MPs, there is an effective threshold of about 8%. Scotland also uses the d’ Hondt method for allocating seats, whidh reputedly is more favourable to larger parties that the StLague system in NZ.

It seems a problem of many description of MMP/AMS that they talk about having constituency elections then about ‘added’ list MPs to achieve proportionality.

But as we know, it is the party votes that determine in MMP/AMS the overall makeup of parliament. So it is simpler to say that we use party votes to determine the overall number of seats in parliament for each party, and THEN fill those seats beginning with electorate/constituency winners, and taking the rest from party lists. (Noting that Scotland uses open party lists so that voters have a choice of list members, but voting papers are more complex).

Once you see it this way, the party votes are what you count first, because they take you straight to the overall result. By contrast the constituency and list results are of mainly local interest.

Two conclusions:
1. Descriptions of AMS/MMP should make more clear that it is party votes that almost solely determine the numbers seats in parliament for each party.
2. Once this is understood, it seems that Scotland could determine much more quickly the overall result of its AMS elections.

Comments relating to the New Zealand MMP threshold:

The use of several regions in Scotland makes for quite high effective thresholds. Many tiny parties have no hope of representation. The system might be made more proportional by having a fixed threshold and offering a second choice of party vote. That would allow every voter to vote for a party representated in parliament. The use of open lists in Scotland makes voting papers, and hence a second choice of party vote, more complicated than is proposed for NZ.

Is there a flaw in the NZ MMP electoral system?

It seems that there is a problem with many implementations of MMP and similar electoral systems.  The problem stems from the use of thresholds to avoid a proliferation of small parties in the representative assembly.

Having a threshold seems innocuous enough, assuming one accepts the premise that it is desirable/important/useful/acceptable to limit the representation of very small parties in parliament.  

It seems that most thresholds are implemented in a very simplistic way.  If a party does not pass the threshold, it is completely excluded from the assembly.   Its votes are discarded.  It has no right to have any paid representatives present, to receive any secretarial or office space support, to speak, or to vote.  

After discarding the votes of under-threshold parties, seats are  allocated generally in proportion to the remaining, qualifying, votes. 

Because of this mode of  operation, the existence of the threshold creates perverse incentives for almost all players.   A vote that was cast for a below-threshold party is a vote taken away from its allied parties and then discarded.   Small emerging parties should be well aware that until they pass the threshold, they are working against their allied parties, and against the chances those allied parties have of forming a coalition government after an election.  Major parties are not immune from these perverse effects.    Major parties need to take into account that apparent support parties, ones of the same side of the left/right divide but below-threshold, are in fact working against the major party’s chances of forming a governing coalition after the election.  So an apparent support party is not something to encourage.  And it is all made more confusing because nobody can be sure in advance which parties will cross the threshold.

So, not only is the threshold something quite high to overcome, but on the way there all parties are disturbed by the perverse effects of a simple threshold.

So the threshold is about much more than the percentage.    It also creates conflicting motivations and loyalties for voters and parties.  Voters are torn between voting for a small party and hence against its allied big party OR  voting for the allied big party and not for their preferred party.    Small parties and their supporters want to encourage voters to support their small party, knowing that they are probably taking votes from the allied big party and wasting them.  Big parties  fear the negative effects of smaller parties that notionally support them.

That explanation was probably confusing.  If so it reflects the confusing and conflicted environment that affects everybody who has connections with small parties in an MMP environment.

But wait there’s more. The MMP party vote does two things.  The first thing is to decide which parties are eligible for seats in parliament.  The second thing is to measure the relative support of each, and to allocate seats in parliament accordingly.  But the voters who voted for under-threshold parties have no say in this allocation.  If we are aiming to measure relative support, it seems unfortunate to leave out up to 8% of voters.

New Zealand’s MMP system uses closed party lists, so the voting paper is very simple.  On this voting paper, adding a second column is easy, to allow each voter a second choice of party vote.  If a voter’s first choice party falls below the threshold, the vote can go to a second choice.  In this way every voter can both nominate a preferred party, and vote for one of the eligible parties.

This second choice eliminates the conflict around small parties and as well allows the party voting to be much more proportional.  And the bonus, for those who think the threshold is important, is that these improvements  can be made without any change to the threshold percentage.

An advantage of this change is that it should help everybody, so perhaps a consensus is achievable without much delay.

There is of course nothing to prevent the threshold being reduced, but that is another question.
More at www.onthethreshold.nz

Consensus for the next step

In order to alleviate the problems with the New Zealand MMP Threshold, a consensus way forward is needed. Two-choice party voting offers that potential consensus. It addresses some of the most important criticisms of the threshold, and makes the voting system much more proportional. And it leaves the threshold percentage unchanged, because there is no consensus on whether or how to change it.

There is a new page on the site, entitled ‘Consensus at last’.