Polls

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This is a hobby project. My hobbies do not include old IEs. Therefore this page does not work in IE8 or lower.

Here I study the polls.

My average

My weighted average of the polls is designed to flatten out trends, so that outliers are somewhat ignored, and only persistent trends accepted. It reports a shift of seats relative to current parliament.

It reports new parties only if they have at least one seat in every poll. This simple rule of thumb helps reduce tiny-party clutter wonderfully.

My average of the polls
Party 2012 Senate Party

The effective number of parties is a measure for the fragmentation of a party system. The highest effective number ever reached in actual elections was 6.7 in 2010.

Current polls

Here’s an overview of the latest poll by each pollster. The Bullish and Bearish columns show the parties that have more than % more or less seats in this poll than in my average. They show the same for the blocks and types, but with a % threshold and a minimum difference of seats.

Current poll overview
Pollster Date Weight Bullish Bearish New parties
I&O Research
()
Een Vandaag
()
Politieke Barometer
()
Peil.nl
()
TNS-NIPO
()

The Weight value gives the relative weight of the poll in the calculation of the Now column above. However, the Now column also uses older polls that fall before the second column’s date, so the average isn’t dependent on these last polls alone.

Parties

See the party profiles for a description of most parties. Below are the ones I never wrote a party profile for.

The OSF (Onafhankelijke Senaatsfractie; Independent Senate fraction) is an amalgam of regional parties that will not enter the national elections.

The PP is the Dutch Pirate Party.

DENK (Think) is currently two Turkish-Dutch MPs from the PvdA who split off and now try to start a party for non-white Dutch. Since they mostly focus on Turkish hobbies such as supporting Erdogan and denying the Armenian genocide I wonder how much success they'll have with non-Turks. It was reported some Moroccan voters may also be on board.

Art1 (Artikel 1; Article 1, the constitutional article concerned with equality before the law) is headed by Sylvana Simons, a black TV personality and former DENK member who was unhappy with support by the (Turkish) DENK leaders and is now independently angling for the black vote. This has never been done before; in general black Dutch vote for one of the regular left-wing parties.

VNL (Voor Nederland; For the Netherlands), is a PVV split-off headed by Jan Roos, one of the initiators of the Ukraine referendum, although it was founded by two PVV MPs who were unhappy with the PVV’s lack of internal democracy.

FvD (Forum voor Democratie; Forum for Democracy) is headed by Thierry Baudet, one of the initiators of the Ukraine referendum, and a fairly intellectual member of the extreme right.

GP (GeenPeil) is the party of right-wing shock site GeenStijl. It plans for direct democracy by requiring its MPs to vote however the party members decide. This will likely be a recipe for internal chaos, in the unlikely case that it will win seats.

VP (Vrijzinnige Partij; Liberal Party but with a bit of translation trickiness) is the vehicle for the sole MP that split off from 50Plus. Will not get any seats.

NW (Nieuwe Wegen; New Ways) is a left-wing split-off from the PvdA that wants less immigration and clearly left economic policies. If you ask how it differs from the SP, except maybe for being a bit more anti-immigration, I’ll have to tell you I don’t know. Likely the voters won’t know, either.

Coalitions

For an introduction to Dutch coalitions I advise you to read this article series that I wrote for the 2010 elections. The details are slightly different today, but the broad overview is still valid.

  1. Overview and general introduction.
  2. The Left coalition.
  3. The Right coalition.
  4. The Centre-right coalition.
  5. The Purple coalition.
  6. The Centre-left coalition.

The coalition tables are automatically generated — they may sometimes show weird coalitions. Still, Dutch politics are in such a state of advanced chaos that even weird coalitions may come to look appealing.

Coalitions with at least a % likelihood according to
Coalition Type Likelihood Polls ch 2012 Senate

A five- or even a six-party coalition is not as remote as it might seem. Not all parties have to send ministers to the cabinet — they can support government from parliament, like Wilders supported Rutte I (VVD+CDA). The left-wing equivalent would be a PvdA+D66+GL government.

Still, such a minority government would have to come to agreements with other parties that promise to support it. This combination of government parties and supporting parties would have to have a majority, and it is likely to be one of the coalitions mentioned here.

Also, while the CDA is still officially excluding Wilders, I’m going to assume the christian-democrats may change their minds. Therefore, PVV+CDA coalitions are now shown in the table, though at 50% of their usual likelihood. (The CDA might change its mind, but it won’t be happy about it.)

Source
Coalition Type Likelihood Polls ch 2012 Senate

I add the likelihood of all coalitions that a party participates in to get at its likelihood to be in government. I do the same for all coalition types and sizes.

Coalition chances
Coalition type
Coalition size
Prime minister

Calculation methods

How do I calculate my average and the coalitions. (Warning: I have zero knowledge of statistics.)

Polls

I treat the polls as follows:

  1. I established weighting factors for the pollsters based on past performance. They are
  2. I also use a decay factor based on the poll’s age. This is an exponential decay function with N0 of 1, t in days, and λ of .
  3. The polls are sorted according to the periods defined in the first table ( days).
  4. For each period I take the polls of one pollster, multiply the individual party scores by the decay factor, and put them in a bucket by party.
  5. I use the combined scores as votes in an election, which yields a average pollster score for this period.
  6. Once I’ve done so for all pollsters I multiply the average pollster scores by the pollster weight and the decay factor of the most recent poll and put them in a bucket.
  7. I again use the combined scores as votes in an election, which now yields my final average.
  8. Election: this is an election according to the normal rules.
    In order to protect the small parties I use the system of highest remainders for rest seats, and I have no electoral threshold.

Coalitions

coalition relations:

Preferred partners
Possible partners
Unlikely or unwilling partners
Excluded parties

The most negative opinion prevails. So if the SP indicates it can work with the VVD, but the VVD says it can’t work with the SP, their relation is Excluded.

The script creates all possible coalitions and then rejects the following ones:

  1. Coalitions with PvdA, CDA, and VVD.
  2. Coalitions with less than seats.
  3. Coalitions of which a subset already has a majority of seats.
  4. Coalitions with parties that have excluded each other. (See sidebar for the current exclusion list.)
  5. Coalitions with two or more parties that have less than seats.
  6. Coalitions whose smallest party has less than seats, unless that party gives the coalition its majority in either parliament or senate.

The table shows the remaining coalitions.

Coalition likelihood

The likelihood of a coalition is calculated by the following formula that I tweaked by hand (there are few theoretical underpinnings here). I don’t doubt I’ll make frequent changes.

The formula is
1/SIZE * MAJORITY * SMALLEST * RELATION * SENATE * CDAPVV

SIZE
the number of parties in the coalition
MAJORITY
the majority of the coalition (seats over 75)
SMALLEST
the size of the smallest party
RELATION
Each pair of parties has a relation from 0 (excluded) to 3 (preferred). The sidebar shows which parties have which relations.
The variable is the sum of the worst relations in the coalition.
(Coalitions in which any two parties have relation 0 are rejected automatically, so that value doesn’t occur.)
SENATE
Is 1 if the coalition has a majority in the senate, if it does not.
CDAPVV
Is when both CDA and PVV are in the coalition, otherwise it is 1.

Once the likelihood of all coalitions has been calculated, the results are treated as votes in an election for 100 seats. This yields the percentages that are shown in the table.

Raw data

There are four pollsters in Dutch politics: the Politieke Barometer, Peil.nl, Een Vandaag, and TNS-NIPO. Here’s the raw JSON data; below are some nice tables.

2011-2015 data are here.

Politieke Barometer

The Politieke Barometer publishes its poll every two weeks on a Thursday.

I trust the Politieke Barometer more than the other pollsters. It has a better score than the others for the right block and the traditional catch-all parties.

Politieke Barometer polls are usually quoted in the press, but don’t get anything near the exposure of Peil.nl polls.

Last Politieke Barometer polls
Party 2012 Party

Peil.nl

Peil.nl publishes its poll every week on Sunday.

Peil.nl is always out for sensational headlines. Protest parties SP and PVV usually poll better with Peil.nl than with the other two, and the same goes for the left block and for small parties.

Maurice de Hond, Peil.nl’s owner and a well-known political commentator in his own right, uses an open Internet poll to which anyone can subscribe. (I have.) This methodology is criticised time and again by the other two pollsters and political scientists, but if we compare his last polls to the election results he doesn’t do significantly worse than the other two. Part of the problem is that he has the best press contacts of the three, and his polls always draw headlines. Besides, if a TV programme needs a political pollster they always ask him. This won’t make him very popular among his colleagues.

Last Peil.nl polls
Party 2012 Party

TNS-NIPO

TNS-NIPO publishes its poll about every two months.

Generally TNS-NIPO is closer to the Politieke Barometer than to Peil.nl, with maybe a tad advantage for the centre parties.

TNS-NIPO polls rarely garner much attention in the press, except in De Volkskrant, which is a partner in this series of polls. That’s probably due to the confused release schedule, and TNS-NIPO’s annoying habit to release some polls only together with the next one.

Last TNS-NIPO polls
Party 2012 Party

Een Vandaag

Een Vandaag publishes its poll every month.

The poll is executed by Intomart GFK, which also polled in 2010 but not earlier, and did the worst job of the four pollsters. It seems even more left-minded than Peil.nl, which is no mean feat. Also, the single issue parties score better than in the other polls.

One incredibly annoying habit this poll has is giving the occasional seat to “other parties” — without making clear which parties. I assign these seats to the Pirate Party, which right now is the only Other party that stands a chance of entering parliament. Of course that’s incorrect, but I don’t know how else to deal with these seats.

Last Een Vandaag polls
Party 2012 Party

I&O Research

I&O Research is a new pollster. I don’t yet know how well it performs, or even how often it will publish polls.

Last I&O Research polls
Party 2012 Party