Open lists in MMP: An option for BC and the experience in Bavaria

One of the options for electoral reform in British Columbia is mixed-member proportional (MMP) representation. The criteria for the potential system allow for a post-referendum decision (if MMP is approved by voters) on whether the party lists should be open or closed. The guide that was sent to all BC voters shows a mock-up of a ballot that looks like New Zealand’s, with closed lists. However, the provincial premier has stated that, if MMP is adopted, lists will be open.

When it comes to lists, it is my opinion that citizens will elect all of the members of the legislature. They will select names that are representative of their communities.

I remain uncertain about the value of open lists under MMP. Is it worth the extra ballot complexity? What additional gain does one get from having preference votes determine order of election for those winning compensatory seats? The MMP Review in New Zealand after the 2011 referendum (in which voters voted to keep MMP) looked at this question extensively. It came down firmly on the side of keeping lists closed.

Nonetheless, the statement by the premier suggests he believes the system is less likely to be chosen if voters expect the lists to be closed. And, given regional districts on the compensation tier, as explicitly called for in the system proposal, the lists would not be too long and thus the ballots not too complex.

It happens that there is one MMP system in existence in which the lists are open. Such a system has been used in Bavaria for quite some time. I actually proposed such a model in a post way back in 2005, quite early in the life of this blog. At the time I had no idea that what I had “invented” was, more or less, the existing Bavarian model.

Of course, Bavaria just had an election. In the thread on that election, Wilf Day offered some valuable insights into how the open lists worked. I am “promoting” selections from Wilf’s comments here. Indented text in the remainder of this post is by Wilf.

The Bavarian lists are fully “open,” and the ballot position has no bearing on the outcome, except to the extent the voters are guided by it, especially seen in voting for the number 1 candidate.

Of the 114 list seats, 31 were elected thanks to voters moving them up the list, while 83 would have been elected with closed lists.

Did the first on the list always get elected? Almost. In the region of Lower Bavaria, the liberal FDP elected only 1 MLA, and he had been second on their regional list.

Did the open lists hurt women? I did not check most results, but the SPD zippers their lists, and I noticed in Upper Palatinate the SPD elected 2 MLAs, list numbers 1 and 3 (two women). Conversely, in Middle Franconia the SPD elected 4 MLAs: 1, 2, 3, and 5 (three men).

Little known fact: a substantial number of voters in Bavaria, being used to voting in federal elections where their second vote is just for a party, blink at the Bavarian ballot, look for the usual space to vote beside the party name, it’s not there, so they put an X beside the party name anyway. A spoiled ballot? No, they count it as a vote for the party. Not a vote for the list as ranked, it does not count for the ranking or for any candidate, but it does count in the party count. Just like Brazil, where a vote for the party is not a vote for the list ranking, except Bavaria does not publicize the option of voting for the party.

Among the more interesting new Free Voter MLAs:

Anna Stolz, lawyer, Mayor of the City of Arnstein; she had been elected Mayor in 2014 as the joint candidate of the Greens, SPD, and Free Voters; the local Greens said they were very proud of her as Mayor. The Free Voter delegates meeting made her number 5 on the state list, but the voters moved her up to second place as one of the two Free Voter MLAs from Lower Franconia.

From Upper Bavaria, the capital region, list #12 was Hans Friedl, with his own platform: “a socially ecologically liberal voice, an immigration law based on the Canadian model, no privatization of the drinking water supply, a clear rejection of the privatization of motorways”). The voters moved him up to #8, making him the last of 8 Free Voters elected in that region.

Note: the comments are excerpted, and the order of ideas is a little different from where they appear in the thread. I thank WIlf for his comments, and for his permission to make them more prominent.

Why “voting system”?

In the earlier entry on the BC referendum, I quoted a passage from the ballot question. It uses the term, voting system.

Yes, “voting system” rather than “electoral system”. Why? What the voters are being asked to decide is clearly what we political scientists mean by electoral system. Is there something objectionable about that term to the general public?

I do not ever use the term, voting system. However, if I did, I would probably understand it to mean the ballot format and other aspects of the process of casting a vote. I would not understand it to include how seats are allocated. An electoral system, as I understand it, is a set of rules that govern voting, counting, and allocation. A whole electoral system is assembly size, district magnitude, tier structure (if not “simple” single-tier), and the specific seat-allocation rule (edit: and the ballot structure). The BC proposals cover all these aspects. It clearly is a referendum on the electoral system. Yet it is officially, “a referendum on what voting system we should use for provincial elections.”

I find it puzzling, although not troubling in any sort of way. (Now, if the term starts creeping into political science, I reserve the right to object.) On the other hand, proponents of change in Canada seem to prefer to call proportional representation “ProRep” rather than PR. I can kind of understand that (“PR” means public relations to civilians). Whenever I see “ProRep” I flinch just a little. But if calling it that helps sell it, I can get over it.

What could we expect from electoral reform in BC?

This week is the beginning of the mail voting period for the referendum on whether to reform the electoral system for provincial assembly elections in British Columbia. The ballot asks two questions: (1) Do you want to keep the current FPTP system or “a proportional representation voting system”: (2) If BC adopts PR, which of three types of PR do you prefer?

The second question offers three choices, which voter may rank: Mixed-Member Proportional (MMP); Dual-Member Proportional (DMP); Rural-Urban Proportional (RUP).

I have reviewed before what these options entails, and will not repeat in detail here. Besides, the official BC Elections site explains them better than I could. What I want to try to get it here is how we might expect BC’s provincial party system to change, were any of these options adopted. To answer that question, I turn, of course, to the Seat Product Model, including the extended form for two-tier systems developed in Votes from Seats.

The punch line is that the various scenarios I ran on the options all suggest the effective number of parties in the legislative assembly would be, on average, somewhere in the 2.46 to 2.94 range, the effective number of vote-earning parties would tend to be in the 2.83 to 3.32 range, and the size of the largest party would be somewhere between 45% and 51% of the seats. Again, these are all on average. The ranges just provided do not mean elections would not produce a largest party smaller than 45% or larger than 51%. Actual elections will vary around whatever is the point prediction of the Seat Product Model for any given design that is adopted. And fine, yet important, details of whichever system is adopted (if FPTP is not retained) will remain to be fleshed out later.

The ranges I am giving are formula-predicted averages, given the inputs implied by the various scenarios. I explain more below how I arrived at these values. The key point is that all proposals on the ballot are quite moderate forms of PR, and thus the party system would not be expected to inflate dramatically. However, coalition governments, or minority governments with support from other parties, would become common; nonetheless, single-party majority governments would not likely disappear from the province’s future election outcomes. As we shall see, one of the proposals would make single-party governments reman as the default mean expectation.

Before going to the scenarios, it is important to see whether the real BC has been in “compliance” with the Seat Product Model (SPM). If it has tended to deviate from expectations under its actual FPTP system, we might expect it to continue to deviate under a new, proportional one.

Fortunately, deviations have been miniscule. For all elections since 1960, the actual effective number of vote-earning parties has averaged 1.117 times greater than predicted. That is really minor. More important is whether it captures the actual size of the largest party well. This, after all, is what determines whether a single-party majority government can form after any given election. For all elections since 1960, the average ratio of actual largest-party seat share to the SPM prediction is 1.068. So it is even closer. For an assembly the size of BC’s in recent years (mean 80.7 since 1991), the SPM predicts the largest party will have around 57.8% of seats. The mean in actual elections since 1991 has been 62.7%. That is a mean error on the order of 4 seats. So, the SPM captures something real about the current BC electoral system.

Going a little deeper, and looking only at the period starting in 1996, when something like the current party system became established (due to the emergence of the Liberals and the collapse of Social Credit), we find ratios of actual to predicted as follows: 1.07 for effective number of vote-earning parties; 1.07 for largest parliamentary party seat share; 0.905 for effective number of seat-winning parties. If we omit the highly unusual 2001 election, which had an effective number of parties in the assembly of only 1.05 and largest party with 96.2%, we get ratios of 0.98 for effective number of seat-winning party and 0.954 for largest party size. The 2017 election was the first one since some time before 1960 not to result in a majority party, and it is this balanced parliament that is responsible for the current electoral reform process.

As for the proposed new systems, all options call for the assembly to have between 87 seats (its current size) and 95 seats. So I used 91, the mean; such small changes will not matter much to the estimates.

The MMP proposal calls for 60% of seats to remain in single-seat districts (ridings) and the rest to be in the compensatory tier (which would be itself be regionally based; more on that later). So my scenarios involved a basic tier consisting of 55 seats and a resulting 36 seats for compensation. Those 36/91 seats mean a “tier ratio” of 0.395 (and I used the rounded 0.4). The formula for expected effective number of seat-winning parties (Ns) is:

Ns=2.5^t(MS)^0.167.

With t=.4, M=1 (in the basic tier) and S=91, this results in Ns=2.81. I will show the results for other outputs below.

For the DMP proposal, the calculations depend on how many districts we assume will continue to elect only one member of the legislative assembly (MLA). The proposal says “rural” districts will have just one, to avoid making them too large geographically, while all others will have two seats by combining existing adjacent districts (if the assembly size stays the same; as noted, the proposals all allow for a modest increase). In any case, the first seat in any district goes to the party with the plurality in the district, and the second is assigned based on province-wide proportionality. For my purposes, this is a two-tier PR system, in which the compensatory tier consists of a number of seats equivalent to the total number of districts that elect a second MLA to comprise this compensatory pool. Here is where the scenarios come in.

I did two scenarios, one with minimal districts classified as “rural” and one with more. The minimal scenario has 5 such districts–basically just the existing really large territorial ridings (see map). The other has 11 such districts, encompassing much more of the interior and north coast (including riding #72, which includes most of the northern part of Vancouver Island). I will demonstrate the effect with the minimal-rural scenario, because it turned out to the most substantial move to a more “permissive” (small-party-favoring) system of any that I looked at.

Of our 91 seats, we take out five for “rural” districts, leaving us with 86. These 86 seats are thus split into 43 “dual-member” districts. The same formula as above applies. (Votes from Seats develops it for two-tier PR, of which MMP is a subset.) The total number of basic-tier seats is 48 (the five rural seats plus the 43 DM seats). There are 43 compensation seats, which gives us a tier ratio, t=43/91=0.473. Ah ha! That is why this is the most permissive system of the group: more compensation seats! Anyway, the result is Ns=2.94.

If we do the 11-rural seat scenario, we are down to 80 seats in the DM portion of the system and thus 40+11 basic-tier seats. The tier ratio (40/91) drops to 0.44. The resulting prediction is Ns=2.61. This does not sound like much, and it really is not. But these results imply a difference for largest seat size between the first scenario (45%) and the second (49%) that makes a difference for how close the resulting system would be to making majority parties likely.

Finally, we have RUP. This one is a little complex to calculate because it is really two different systems for different parts of the province: MMP for “rural” areas and STV for the rest. I am going to go with my 11 seats from my second DMP scenario as my “rural” area. Moreover, I understand the spirit of this proposal to be one that avoids making the districts in rural areas larger than they currently are. Yet we need compensation seats for rural areas, and like the full MMP proposal, RUP says that that “No more than 40% of the total seats in an MMP region may be List PR seats”, so this region needs about 18 seats (the 11 districts, plus 7 list seats, allowing 11/18=0.61, thereby keeping the list seats just under 40%.) That leaves us with 91-18=73 seats for the STV districts. The proposal says these will have magnitudes in the 2-7 range. I will take the geometric mean and assume 3.7 seats per district, on average. This gives us a seat product for the STV area of 3.7*73=270.

In Votes from Seats, we show that at least for Ireland, STV has functioned just like any “simple” PR system, and thus the SPM works fine. We expect Ns=(MS)^.167=2.54. However, this is only part of the RUP system. We have to do the MMP part of the province separately. With just 11 basic-tier seats and a tier ratio of 0.39, this region is expected to have Ns=2.13. A weighted average (based on the STV region comprising 80.2% of all seats) yields Ns=2.46.

The key point from the above exercise is that RUP could result in single-party majority governments remaining the norm. Above I focused mainly on Ns expectations. However, all of the predictive formulas link together, such that if we know what we expect Ns to be, we can determine the likely seat-share of the largest party (s1) will be, as well as the effective number of vote-earning parties (Nv). While that means lots of assumptions built in, we already saw that the expectations work pretty well on the existing FPTP system.

Here are the results of the scenarios for all three output variables:

System Expected Ns Expected Nv Expected s1
MMP 2.81 3.19 0.46
DMP1 2.94 3.32 0.45
DMP2 2.61 3.01 0.49
RUP 2.46 2.87 0.51

“DMP1” refers to the minimal (5) seats considered “rural” and DMP2 to the one with 11 such seats. If we went with more such seats, a “DMP3” would have lower Ns and Nv and larger s1 than DMP2, and the same effect would be felt in RUP. I did a further scenario for RUP with the MMP region being 20 districts, and wound up with Ns=2.415, Nv=2.83, s1=.52; obviously these minor tweaks do not matter a lot, but it is clear which way the trend goes.And whether any given election is under or over s1=0.50 obviously makes a very large difference for how the province is governed for the following four years!

I would not really try to offer the above as a voter guide, because the differences across systems in the predicted outputs are not very large. However, if I wanted to maximize the chances that the leading party would need partners to govern the province, I’d probably be inclined to rank MMP first and RUP third. The latter proposal simply makes it harder to fit all the parameters together in a more than very marginally proportional system.

By the way, we might want to compare to the BC-STV proposal that was approved by 57% of voters in 2005 (but needed 60%, and came up for a second referendum in 2009, when no prevailed). That proposal could have been expected to yield averages of Ns=2.61, Nv=3.0, and s1=.49. By total coincidence, exactly the same as my DMP2 scenario.

A final note concerns the regional compensation in the MMP proposal vs. province-wide in DMP. In an on-line appendix to Votes from Seats, I explored whether regional compensation in the case of Scotland produces a less permissive system than if compensation were across all of Scotland. I concluded it made no difference to Ns or s1. (It did, however, result in lower proportionality.) Of course, if it made a difference, province-wide would have to be more favorable to small parties. Thus if this were a BC voter’s most important criterion, DMP might pull ahead of MMP. However, the benefit on this score of DMP is greater under a “low-rural” design. The benefit of DMP vanishes, relative to MMP, if the system adopted were to be one with a higher share of seats marked as rural. I certainly am unable to predict how the design details would play out, as this will be left up to Elections BC.

The bottom line is that all proposals are for very moderately proportional systems, with MMP likely the most permissive/proportional on offer.

BC electoral reform options for referendum

The electoral-reform process in British Columbia has advanced another step with the Attorney General’s release of recommendations. The existence of this process is a product of the deal struck after the 2017 election, which resulted in a minority NDP government, backed by the Green Party.

In either October or November, there will be a province-wide vote consisting of two questions: First, do you want to keep the current FPTP system or replace it with a proportional system? Second, which of three PR options would you prefer if the province were to adopt PR? The second part will permit voters to rank-order their choices.

The choices being put to the voters are (using the names given in the recommendations):

Dual-Member PR (DMP)

Mixed-Member PR (MMP)

Rural-Urban PR

I will take the three in order of most familiar to least.

Readers of this blog are probably generally pretty familiar with what MMP is. The short version is: a system in which some percentage of seats (the proposal is for no more than 40%) are elected as “compensatory” list seats, while the rest continue to be elected as under FPTP, in single-seat districts (ridings) by plurality. The key feature is the compensatory nature of the process, so that any party’s number of seats in the provincial assembly are roughly proportional to its province-wide votes. Any seats the party wins in individual ridings are deducted from this total, and remaining seats a party is entitled to hold under the proportionality principle come from the list. It should be noted that the report says “List PR seats are to be allocated within defined regions, not on a province-wide basis.” This could limit proportionality somewhat, but this proposal is likely to be the most proportional of the three (unless perhaps if the compensation regions are quite small).

Rural-Urban PR is mostly single transferable vote (STV), but in the rural parts of the province MMP would be used. This is an unusual system in that it actually is two electoral systems, depending in where you are in the province: STV in urban and “semi-urban” areas, but MMP elsewhere. Under STV, voters rank candidates, but under MMP it seems that it would remain plurality. The logic is to prevent rural ridings from being significantly larger than they are now–one of the concerns raised with “BC-STV” when it was proposed in the province’s previous electoral reform process. The provision for MMP compensation regions in rural areas is obviously an effort to allow for proportional representation even in the areas where the districts will be single-seat. The proposal suggests district magnitudes for the STV regions of 2-9, with a preference for the higher end of that range.

Both MMP proposals–the full province-wide one or the rural component of Rural-Urban PR–could have either a single vote or two votes. The proposal explicitly leaves this (important!) detail to the legislature after the referendum. If there were one vote, then votes for candidates in single-seat ridings would be aggregated by party for the purposes of carrying out proportional compensation (which, for Rural-Urban, would be taking place only over the regions in which the single-seat districts were located). With a two-vote MMP (as found in Germany and New Zealand), voters can vote directly for a list of their preferred party, and thus vote for a party that is different from that of their preferred local candidate. Yet another feature to be left to the legislature to decide would be whether lists would be closed (as is typical for MMP systems), open, or flexible (also known as semi-open, but misleadingly called in the recommendations “open list with party option”).

DMP is a system not actually used anywhere (but see the earlier P.E.I. proposal), and it is a bit complex. In general, each district would elect two members, although the recommendations allow that the “largest rural districts could remain unchanged as single-member districts.” Each party could nominate two candidates, and they would be ranked by the party. Thus we have a closed-list system. Voters would cast a single party vote. The first seat in each 2-seat district would be won by the first-ranked candidate on the party with the most votes in the district. The second seat would actually be allocated based on province-wide votes. It is thus a two-tier compensatory closed-list PR system. How would the assignment of the compensatory seats to districts–given that there is no separate list or compensation district–be done? The proposal says only, “The process for allocating the second seat in each district is fairly complicated.” (Perhaps it would be something like the provisions in Slovenia or as an option for parties in Denmark.)

DMP ensures that all candidates, even those elected on province-wide votes, would represent a riding. It also ensures that one member in each 2-seat riding is elected based on the riding’s own votes. (Exception: it seems there would be a 5% threshold for any party to win seats under any of the list-based provisions being proposed; if that is correct, then it is conceivable that a party could win a plurality of votes in some riding but not be entitled to a seat.)

A puzzling aspect of DMP is the one on independents. If an independent places first in a district, that candidate is elected. That is straightforward enough. However, it is also the case that if an independent places second, that candidate is elected and “the district is removed from the remainder of the second-seat allocation process.” I don’t understand the logic of that provision.

Each proposal allows for the assembly to be increased from its present 87 members up to a maximum of 95, but does not require that the assembly size be increased.

An observation: Why not do DMP with open lists? Have the voter vote for a candidate, rather than a party. It would be a lesser break with FPTP while still being quite proportional. A potential answer: it could mean the candidate with the most personal votes is not elected (because that candidate is on a party that is overall less popular than another in the district). That could be addressed by making it more like MMP–the leading candidate wins the first seat, but that seat is deducted from the compensation entitlement. Otherwise, the DMP provisions would apply. It is interesting that the DMP proposal is explicitly closed list, whereas the list type in the MMP variants would be left up to the legislature.

Any of these systems would seem like a clear improvement for BC. Rural-Urban is an odd mix, but it could work. MMP is proven. DMP is unusual but not based on wholly unknown principles.

(For further reading, see On Elections or Sightline)

BC deal between NDP and Greens

In the wake of British Columbia’s provincial assembly election, which did not result in a single-party majority, a deal has been stuck that would see the government change. The NDP (41 seats) and the Greens (3) would topple the incumbent Liberals (43).

It is a “confidence and supply” arrangement. That is, the NDP and Greens are not forming a coalition cabinet; rather, the Greens are promising support to the NDP to form and maintain a minority government. The deal is intended to last for four years.

Details remain scant at this point, but regarding Greens’ priorities, the Globe and Mail (second link above) reports that the party

had set out three “deal breakers” that include official party status, campaign finance reform and proportional representation, although other issues, including the party’s opposition to several Liberal resource priorities, also would have factored into such talks.

BC 2017: Non-Duvergerian watch

British Columbia votes for its provincial assembly on 9 May. Eric Grenier’s vote and seat projections at CBC suggest it could be a “non-Duvergerian” outcome, especially in the votes. The NDP looks likely to win a majority of seats, manufactured by the electoral system, as its votes are likeliest to stay below 45%. The Liberals are running well behind, but are also likely to be over-represented due to their more efficient votes distribution: Grenier’s average projection for the party would put them on just under 35% of votes but 39% of seats.

The non-Duvergerian aspect of the election is the Greens: average projection of 20% of the votes, which is on the high side for a third party under FPTP. The mechanical effect will crush them, however: average seats only 2 of 87. That, of course, is “typical” FPTP.

Where things get interesting is if the Greens rise even just a few percentage points. The “high” projection takes their votes up only to around 23% but their seats to 12 or more (around 14%)! Clearly, they are running second in many districts–particularly on Vancouver Island.

The reason this pattern is non-Duvergerian is that the so-called Duverger’s law says voters tend not to want to waste their votes on a third party. They should “coordinate” with the more-preferred of the two big parties. Further, this defection should be more likely after the third party has suffered from the mechanical effect of FPTP in past elections, as the Greens in BC have. Instead, their support is evidently growing.

But there is not much incentive to choose between the major parties when you have three-party competition throughout much of the province, and the third party could win a significant number of seats even if it stays well below 50% in the districts where it is most viable.

The BC NDP platform promises: “We’ll hold a referendum – and campaign for the “yes” side – on replacing our outdated voting system with a proportional one.”

Will they follow through if FPTP delivers them a majority?

Update: The tracker of where the party leaders are campaigning is interesting. Of course, there is much emphasis on swing districts, particularly for the NDP. However, this quotation from Richard Johnston (UBC political scientist) is spot on:
“You do have to campaign everywhere; you have to validate the existence of your candidates.” In Chapter 10 of Votes from Seats (forthcoming, Cambridge University Press), Rein Taagepera and I refer to this phenomenon as the “embeddedness” of districts in nationwide (here, provincewide) politics. We do not consider non-Duvergerian districts to be quite the puzzle that others do, because we expect voters to be more oriented towards the aggregate outcome than towards their own district, and parties to care about “showing the flag” even in districts they may not be very likely to win.

Brexit vs. BC-STV: Help with my principles!

As I noted earlier, I happened to be in British Columbia while the British were voting to leave the EU.

[Note: If you want to make general comments on Brexit and what happens next, please comment at the earlier thread. I’d like to keep this one on the narrower topic raised here.]

I never liked the BC-STV vote having been “defeated” in 2005 despite a clear majority (57%), due to a threshold of 60% having been set. But I do not like the UK “mandate” to leave the EU by a vote of 51.9%.

Is there a principle that reconciles my two positions? Or do I just have no principles regarding referendums*, and assess the rules for passage by whether I like what is being proposed? Help, please!

(I have written about referendum approval thresholds before.)

________

* Other than that, in general, I’d rather not have them. I rather like representative democracy and deliberative institutions.