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

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

Inquiry into 2020 election

I have just learnt from facebook that the Justice select committee of parliament is holding an inquiry into the 2020 election. This is apparently something routine after each election. Unfortunately the closing date for submissions was 6 April 2021, so I missed it by a week or so.

From what I have read, the problem of wasted votes creates a barrier to participation in the electoral process. In the 2020 election, about 8% of party votes were disregarded because the voter voted for a party that did not pass either of the thresholds, being 5% or an electorate seat.

Young voters are likely to be interested in new ideas and new parties. But we have a system that disenfranchies anybody who votes for a party that does not pass one or other threshold. This disenfranchisement of minor party voters, perhaps mostly young voters, has a discouraging effect on voter participation.

MMP aims to be a proportional system. But bizarrely we have chosen to disenfranchise a small but significant proportion of voters by discarding their votes. This is a severe deficiency in our supposedly proportional electoral system.

And the problem is not one of the size of the threshold. Reducing the threshold would indeed reduce the problem, and eliminating the threshold would eliminate the problem.

But the problem can be better eliminated by giving voters a second choice of party vote. This solution means that every voter can have a say in the makeup of parliament, as well as expressing support for a minor party.

The two-choice system for party voting effectively decouples the size of the threshold from the issue of wasted votes. We can retain MMP with the threshold at whatever level we want, and still have a highly proportional electoral system.

Have we been barking up the wrong tree?

New Zealand seems to have been barking up the wrong tree for much of the last 25 years looking for a solution to the MMP threshold problem.  No good solution has been identified, and MMP review recommendations remain unimplemented.  

But there is a very simple, easy to understand solution that keeps the threshold but eliminates the problems.

Give voters a second choice of party vote.  If a voter’s first choice party does not pass either threshold, their vote goes to their second choice party.    Voters are advised to make one of their  choices for a party that is certain to pass one of the thresholds.  Nothing else changes.

This solution is easy to understand, easy to implement, and does away with the problems.

Many, perhaps most, voters know which major party they want to see lead the next government.   Many also want to support a small party, but cannot know whether that small party will pass a threshold for gaining seats in parliament.  If they do not vote for the small party, nobody ever knows they supported it.  If they do vote for a small party that misses the threshold, they have no say in government formation.  Many voters struggle with this choice every election.

The second-choice system allows voters to clearly state the party they want to see represent them in parliament, but also have a say in government formation if their preferred party does not pass a threshold

The second choice of party vote requires a second column on the party vote part of the voting paper.  Once it is clear which parties will pass a threshold, each polling place can prepare its own results table.  Results for any grouping of polling places, electorate, region, island, national, specials, overseas, etc are easily obtained by simply adding up the results from the polling places involved.

Ideas like this were suggested by numerous submitters to the 2012 MMP review, and a few described a system in detail.  The proposal here is a little different in that it simplifies the allocation of second choices.  The message is to choose who you like,  for the first choice.  If you think this party might not pass the threshold, make a second choice for a party that will pass.

The second choice has the same limitations as the present vote.  The vote only counts if it is for a threshold passing party.

This change  takes away all the problems with the existing threshold.  People can express support for a small party, and play a part in deciding the next government.

Nobody needs to worry that votes for small parties may be wasted.  Even if a small party does not pass a threshold, its true level of support is publicly known, and its supporters still have a say in government formation.

This change considerably clears the air for everybody with an interest in the election.  Big parties get to keep the threshold they believe is important.  No votes need to be wasted.  Small parties are still excluded from being allocated seats in parliament, but their votes are recorded and their voters still have a say through their second choice.  The big problem of a party just missing the threshold and so changing the lead party in government is gone.  The system presents a much lower barrier to entry to small parties, while still preventing a proliferation of small parties in parliament.

The example results table shows a hypothetical situation where two small parties just miss the 5% threshold.  With the two-choice system, voters for those small parties have their second choices counted instead.

Listening to voters under MMP

When people vote in an MMP election, what is their message?

Some might say:

  • I would like to see (say) the Maori Party in parliament, but I certainly want a left-leaning government. OR
  • I would like to see (say) the TOP Party in parliament, but I certainly want a right-leaning government.

I think that many people in NZ see elections in this way. But they cannot vote accordingly.

Unfortunately with the present MMP system, you can only say one of:

  • I’d like to see (say) the Maori Party in parliament, but I’m worried they may not pass the threshold and then my vote would be wasted, so I will vote Labour because I want a left- leaning government.
  • I’d like to see (say) the TOP Party in parliament, but I’m worried they may not pass the threshold and then my vote would be wasted, so I will vote National because I want a right-leaning government.
  • I’d like to see (say) the TOP Party in parliament, but if they miss the threshold, I have no further interest in the result of the election.
  • I’d like to see (say) the Maori Party in parliament, but if they miss the threshold, I have no further interest in the result of the election.

I think many people choose one of the first two. Getting a government that leans their way is more important than supporting their preferred party.

There are relatively few that have no further interest in the result if their preferred party does not reach the threshold.

I think that many people are not happy with this. They would prefer to be able to express both their support for a preferred party, AND to have a say in which way the elected government leans.

The two-choice party vote system allows voters to express what are common views:

I want to support a smaller party. But if that party does not pass the threshold, I do not want my vote wasted. I want my vote instead to go this other party.

And what is perhaps surprising: this is very easy to do. An extra column on the party voting paper is all that needs to be visible to the voter. The voter can place a tick in that column, if they want to. Vote counting is fractionally more complicated.

But now we have available the options that (I say) most people want.

History of MMP results

I have created a report to show the party vote results for all nine MMP elections up to 2020, using a consistent format. The information comes from the official site electionresults.org.nz where the results of each election are provided but in various different formats. It provides for each party at each MMP election the number of party votes they received, the number of electorates won. My report shows which parties passed one or other of the thresholds (electorate seat won, at least 5% of party votes), and thus how many votes were wasted because parties did not pass either threshold.

The report can be seen here mmphistoryreport.pdf I believe that I have interpreted and transferred the data correctly.

From the report one can see:

  • That the wasted votes vary between 1.3% (2005) and 7.8%(2020), with an average of 5.4%.
  • The rate of wasted votes is very variable. It was very low in 2005 when there were many minor parties in parliament, many having won just one electorate seat. It was high in 2020, small parties having benefitted from a reduced National Party vote, without crossing a threshold.
  • The 2008 election would have been extremeely close between left and right leaning parties, had the threshold been 4% instead of 5%.
  • The larger numbers of wasted votes have generally been associated with a party gaining about 4% of the party vote, and thus having its votes wasted.
  • This suggests that the two choice system could reduce wasted votes from the present 5% to less than 1%. This is useful, but the main value of the two choice system is to reduce the risk of wasted votes, which is commonly seen as a real obstacle to voting for or working with small parties.