Is AV just FPTP on steroids?

In debates over electoral systems in Canada, one often hears, from otherwise pro-reform people, that a shift to the alternative vote would be worse than the status quo. It is easy to understand why this view might be held. The alternative vote (AV), also known as instant runoff (IRV), keeps the single-seat districts of a system like Canada’s current first-past-the-post (FPTP) system, but replaces the plurality election rule in each district with a ranked-ballot and a counting procedure aimed at producing a majority winner. (Plurality winners are still possible if, unlike in Australia, ranking all candidates is not mandatory. The point is that pluralities of first or sole-preference votes are not sufficient.)

Of course, the claim that AV would be FPTP on steroids implies that, were Canada to switch to AV, the current tendency towards inflated majorities for a party favored by less than half the voters would be even more intensified. This is plausible, inasmuch as AV should favor a center-positioned party. A noteworthy feature of the Canadian party system is the dominance, most of the time, by a centrist party. This is unusual in comparison with most other FPTP systems, notably the UK (I highly recommend Richard Johnston’s fascinating book on the topic). The party in question, the Liberal Party, would pick up many second preferences, mainly from the leftist New Democratic Party (NDP) and so, according to the “steroids” thesis, it would thus win many more seats than it does now. It might even become a “permanent majority”, able to win a parliamentary majority even if it is second in (first-preference) votes to the Conservatives (who thus win the majority or at least plurality of seats under FPTP). The “steroids” claim further implies that the NDP would win many fewer seats, and thus Canada would end up with more of a two-party system rather than the multiparty system it has under FPTP.

There is a strong plausibility to this claim. We can look to the UK, where AV was considered in a referendum. Simulations at the time showed that the Liberal Democrats would stand to benefit rather nicely from a change to AV. While the LibDems are a third party, heavily punished by the FPTP electoral system even when they have had 20% or so of the votes, what they have in common with the Canadian Liberals is their centrist placement. Thus, perhaps we have an iron law of AV: the centrist party gains in seats, whether or not it is already one of the two largest parties. An important caveat applies here: with the LibDems having fallen in support since their coalition with the Conservatives (2010-15), the assumptions they would gain from AV probably no longer apply.

On the other hand, we have the case of the Australian House of Representatives, which is elected by AV. There, a two-party system is even stronger in national politics than in the FPTP case of the UK, and far more so than in Canada. (When I say “two party” I am counting the Coalition as a party because it mostly operates as such in parliament and its distinct component parties seldom compete against one another in districts.)

It is not as if Australia has never had a center-positioned party. The Australian Democrats, for example, reached as high as 11.3% of the first-preference votes in 1990, but managed exactly zero seats (in what was then a 148-seat chamber). Thus being centrist is insufficient to gain from AV.

Nonetheless, the combination of centrism and largeness does imply that Canada’s Liberals would be richly rewarded by a change to AV. Or at least it seems that Justin Trudeau thought so. His campaign promised 2015 would be the last election under FPTP. While he did not say what would replace it, he’s previously said he likes a “ranked ballot” and he pulled the plug on an electoral-reform process when it was veering dangerously towards proportional representation.

Still, there are reasons to be somewhat skeptical, at least of the generalization of the Australian two-party experience. The reasons for my caution against the “steroids” view are two-fold: (1) the overlooked role of assembly size; (2) the ability of parties and voters to adapt.

Assembly size is the most important predictor of the size of the largest party, disproportionality, and the effective number of seat-winning parties in countries that use single-seat districts. (It is likely relatively less important when there are two rounds of voting, as in France, but still likely the most important factor.) This is a key conclusion of Votes from Seats. It is thus important not to overlook the fact that Australia has an assembly size considerably smaller than Canada’s. In the book, Taagepera and I show that Australia’s effective number of seat-winning parties and size of largest parliamentary party are almost what we would expect from its assembly size, even if FPTP were used. (See also this earlier post and its comment thread; how close it is to expectation depends on how we count what a “party” is.) The data are calculated over the 1949-2011 period, and the effective number of parties has been just 1.10 times the expectation from the Seat Product Model (which is based only on assembly size when single-seat districts are used). Similarly, the average largest party has been 93% of the expected size (averaging 54.2% of seats when we would expect 50.5%).

Thus we do not need to invoke the alleged steroids aspect of AV to understand the dominance of two parties in Australia. But this does not mean it would not make a difference in Canada. Consider that the current effective number of parties and size of the largest party in that country, averaged over a similar period, are also just about what we should expect. The multipartism, including periodic minority governments, that characterize Canada are not surprising, when you use the Seat Product Model (SPM). They are surprising only if you think district magnitude is all that matters, and that FPTP is FPTP. But it isn’t! An electoral system using the FPTP electoral rule with an assembly of more than 300 seats is a different, and more multiparty-favoring, electoral system than one with 150 seats. Replace “FPTP” in that sentence–both occurrences–with “AV” and it is surely still true.

But what about the centrist party, the Canadian Liberals? Surely AV would work differently in this context, and the Liberals would be a much more advantaged party. Right? Maybe. If so, then it would mean that the SPM would be overridden, at least partially, in Canada, and the largest party would be bigger than expected, for the assembly size, while the effective number of parties would be lower than expected. Of course, that’s possible! The SPM is devised for “simple” systems. AV is not simple, as we define that term. Maybe the SPM is just “lucky” that the one country to have used AV for a long time has the expected party system; or it is lucky that country has the “correct” assembly size to sustain two-party dominance. (Australia is the Lucky Country, after all, so if the SPM is going to get lucky one place, it might as well be Australia.)

This is where that other factor comes in. While no one has a crystal ball, I am going to go with the next best thing. I am going to say that the SPM is reliable enough that we can predict that, were Canada to have AV, it would have an effective number of parties around 2.6 and a largest party with around 48% of seats. In other words, just about where it has been for quite some time (adjusting for the House size having been a bit smaller in the past than it is now). Note these are averages, over many elections. Any one election might deviate–in either direction. I won’t claim that a first election using AV would not be really good for the Liberals! I am doubting that would be a new equilibrium. (Similarly, back in 2016 I said my inclination would not be to predict the effective number of parties to go down under AV.)

Parties and voters have a way of adapting to rules. Yes the Liberals are centrist, and yes the Conservatives are mostly alone on the right of the spectrum (albeit not quite as much now, heading into 2019, as in recent years). But that need not be an immutable fact of Canadian politics. Under AV, the Liberals might move leftward to attract NDP second preferences, the NDP center-ward to attract Liberal and even Conservative second preferences, the Conservatives also towards the center. It would be a different game! The Greens and other parties might be more viable in some districts than is currently the case, but also potentially less viable in others where they might win a plurality, but struggle to get lower ranked preferences. The point is, it could be fluid, and there is no reason to believe scenarios that have the largest party increasing in size (and being almost always the Liberals), and correspondingly the effective number of parties falling. With 338 or so districts, likely there would remain room for several parties, and periodic minority governments (and alternations between leading parties), just as the SPM predicts for a country with that assembly size and single-seat districts.

As I have noted before, it is the UK that is the surprising case. Its largest party tends to be far too large for that huge assembly (currently 650 seats), and its effective number of seat-winning parties is “too low”. Maybe it needs AV to realize its full potential, given that the simulations there showed the third party benefitting (at least when it was larger than it’s been in the two most recent elections).

Bottom line: I do not buy the “FPTP on steroids” characterization of AV. I can understand were it comes from, given the presence in Canada of a large centrist party. I just do not believe Liberal dominance would become entrenched. The large assembly and the diversity of the country’s politics (including its federal structure) both work against that.

I agree with electoral reformers that PR would be better for Canada than AV. I also happen to think it would be better for the Liberals! But would AV be worse than FPTP? Likely, it would not be as different as the “steroids” claim implies.

New Brunswick 2018

The Canadian province of New Brunswick held its provincial assembly election on 24 September. The result is an assembly with no majority of seats.

The incumbent Liberal government, which won a majority in 2014 but had fallen to minority in the interim, came in second place in seats but first in votes in the 2018 election. The main opposition, Progressive Conservatives (PC), won just one seat more, and are short of a majority.

The Liberals have 21 seats on 37.8% of the vote, the PCs 22 seats on 31.9%, while a previously underrepresented party, People’s Alliance (PANB) and the Green Party each won three seats. The PANB won 12.6% of the vote and the Greens 11.9%. The NDP won 5% of the votes, but no seats.

The district-level results are interesting. The People’s Alliance leader, Kris Austin, won a clear majority (54.6% in Fredricton-Grand Lake, with the runner up being a PC incumbent with only 27.7%; in 2014, Austin had lost to the PC candidate 28.8%-28.5%!). In another riding, Fredricton-York, the PANB candidate defeated another PC incumbent, 33.7%-30.9%. The third PANB winner was in Miramichi and won 57.0% to 35.0% over a Liberal. I counted six other seats in which a PANB candidate came in second, although only one of these was really close (Southwest Miramichi-Bay Du Vin, where a PC has 35.4% over the PANB on 35.0%). The three districts the PANB won and the one where they are very narrowly behind, are all contiguous. It is clearly a regional party; it ran in 30 of the 49 ridings.

As for the Green winners, leader David Coon, who was their first elected MLA (2014) retained his seat easily, 56.3%-20.1% over a Liberal. In Kent North their candidate won 45.9%-37.4% over a Liberal. In Memramcook-Tantramar, Megan “Landslide” Mitton won by 11 votes (38.3%-38.2%) over a Liberal.  It seems there are two districts in which a Green came in second, but neither was close; in both cases the Liberal winner had a majority. The Green wins are not contiguous districts; the leader represents a seat in Fredricton and the other two are geographically large coastal districts. (See results and map at CBC; these are, of course, not necessarily final at this point, and there is even one Liberal lead of just 10 votes over a PC.)

It is not clear what the government result will be. I’ve been listening to CBC on the post-election discussions, and it seems the Greens have rejected a possible coalition with the Liberals; given that the results revised above suggest the Liberals are the Greens’ main opponent at district level, this reluctance has some (FPTP-based) logic to it. The Conservatives have said they will vote down a Liberal throne speech (not surprisingly). The PCs have declared all of their members are unwilling to stand for Speaker, and the Liberals also do not want any of their own to take the post. Without a Speaker, no other business can be transacted. So, for now at least, we have a stand off. (Update: The Liberal leader and current Premier Brian Gallant has said his party will put forth a candidate for Speaker today.)

It is worth noting that New Brunswick has quite a record of unusual election outcomes, and electoral-reform proposals. Just click “N.B.” at the bottom of this post to see previous entries on this recent history. Of particular interest is the time the Liberals took power thanks to a plurality reversal and promptly called off the previous (Conservative) government’s planned referendum on adopting MMP. Maybe it is time to dust off those proposals. The voters of the province seem unwilling to play the old FPTP game the way “the law” says to play it.

Quebec 2018

Because it took place on Shemeni Atzeret, a very big Jewish holiday that “closes” the festival of Sukkot (but is separate from it), I totally missed that Quebec was having a provincial general election.

The result is being called a “surprise”. The Coalition Avenir Quebec (CAQ) won a majority of seats (74 of 125) on just 37.4% of the votes. That is 59.2% of the seats, for an advantage ratio of 1.58, which is certainly on the high side.

The incumbent Liberals won 32 seats (compared to 70 at the last election) on 24.8% of the votes (compared to 41.5% last time). Quebec Solidaire (QS) has 10 seats on 16.1% and the Parti Quebecois (PQ), which was governing as recently as 2014, a mere 9 seats on 17.1% of the vote.

You might note that this is rather far from a “Duvergerian” outcome. It is, however, a “typical” FPTP result, given the presence of a multiparty system: The plurality party won a manufactured majority.

The regional distribution of party support was critical to the outcome, as is also a common feature of FPTP elections. CTV has the list of districts (ridings) and the winner’s percentage of the vote. Not surprisingly, many were won with well under 40% of the vote. An example is Abitibi-Ouest, where the CAQ winner earned 34.1% of the vote and a margin of 195 votes over a PQ candidate. Some other close results also were CAQ over PQ: Bourget, where the winner had a mere 27.6% of the votes and the PQ candidate was 500 votes behind; Ungava (45-vote margin with only 26.5%). On the other hand, there was Iles-de-la-Madeleine, decided in favor of the PQ by only 21 votes over a Liberal candidate (the winner won 38.7%). Then there was Duplessis, decided by 126 votes, with the PQ on top (34.3%) and CAQ second. The Liberals had some narrow victories, too (such as Gaspé, 33.8%, 132 votes over the PQ; Laval-Des-Rapides, 31.6%, 297 votes over the PQ). It is a pretty wild district-level picture!

The opposition parties going into the election–CAQ, QS, and PQ (plus the Greens)–had committed to a platform calling for a change of electoral system to proportional representation, apparently MMP.  I can’t say for sure–no doubt some readers will know–but I’d tend to assume this was promised under the assumption of a no-majority assembly. (The Liberal leader reiterated shortly before the election that he was not on board, even in the event his party would have formed a minority government after this election.) A real test of the CAQ is whether it has now had an overnight conversion to the virtues of FPTP, or whether the commitment will be effectively binding. The list above of CAQ victories over the PQ certainly shows that, to some significant degree, the parties are rivals given the dynamics of the current electoral system. Quebec–and Canada–has seemed at the cusp of electoral reform before…

(Note: There is already some ongoing discussion of this election at a previous post about the 2014 election.)

Ontario 2018: Dramatic polling shift and an anomaly watch

With just over a week to go till the provincial assembly election of 7 June, polls in Ontario have shifted quite dramatically.

Here is what it looked like, according to the CBC Poll Tracker, on 18 May:

The Progressive Conservatives (PC) were well ahead in votes, and strongly favored to win a manufactured majority of seats with 41% of the vote. It’s good to be a 40-percent party under FPTP, especially when you are in a highly non-Duvergerian party system with two other large parties splitting most of the remaining three fifths of the vote. The New Democrats (NDP) were far behind, at not quite 30%, and the incumbent Liberals not even polling a quarter of the votes.

Ten days later, here is how things have shifted:

Well, it is a little more “Duvergerian” in that it looks like a close race between two parties, the PCs and the NDP. But not anything like your supposed lawlike “two-party system”, with a third party at over 20% and the fourth just below 5%.

As to what has has led to this shift, and the possible echoes of the 1990 election (which resulted in the only NDP government in the province’s history, to date), see Eric Grenier’s explanation at CBC.

This being a FPTP system, even with a polling lead as of now that is almost two percentage points, it is not as simple as the party with the most votes being assured of governing (whether with a majority, minority, or as head of a coalition). Note how in today’s projection the NDP is favored to win fewer seats than the PCs and the latter party is still quite likely to win a majority of seats.

Thus I hereby declare Ontario 2018 to be on anomaly watch.


Malaysia election 2018

Malaysia’s election counting is underway, and reports abound that the opposition alliance has won. (Opposition, but led by an aging former prime minister who defected from the long-ruling party.)

Malaysia uses plurality in single-seat districts (FPTP), and is (in)famous for its severe malapportionment. It will be interesting to see how big the vote swing is, but the seats outcome apparently will be close. The BBC report linked above says the opposition has 115 seats out of 222.

Sierra Leone 2018

[See caveat in comments about the electoral rules of the earlier elections. For now, I am not changing the post, even though I should re-do it with averages only from the FPTP elections.]

On Sunday, Sierra Leone held its presidential runoff. Sierra Leone is one of those examples of a relatively rare combination: presidentialism with an assembly elected by plurality in single-seat districts. Some of the other examples of this combo are also found in West Africa, including Ghana and Liberia. In this entry, I will consider the effects of Sierra Leone’s institutions on the party system, applying some of the logical models of Votes from Seats.

The runoff rule used for the presidency is even rarer (unique?). A second round is required if the leading candidate in the first round does not reach 55% of the valid votes (Art. 42.2.e of the constitution of 1991).

Julius Maada Bio of the Sierra Leone People’s Party (SLPP) won 43.3% in the first round on 7 March. The runner up was Samura Kamara of the All People’s Congress (APC), with 42.7%. This was the country’s closest contest thus far since the current democratic institutions were inaugurated in 1996.

Sierra Leone has had one president during this time period who was elected with less than 55%. In 2007, Ernest Bai Koroma of the APC won with just 54.62%. However, this was in the runoff. He had 44.3% (to 38.3% for the runner up) in the first round. And herein lies the real oddity: One might wonder why it is OK to elect a president with just half of the votes, plus one, in a two-candidate runoff, but a total falling between 50% (plus one) and (one vote under) 55% would not be sufficient to win in a single round.

So far Sierra Leone has not had an election in which the first-round leader was in that 50-55% grey zone. Dating to 1996, first-round leaders’ vote percentages have been 35.8, 70.1, 44.3, 58.7, and 43.3

Sunday’s runoff (results for which will not be known for about a week) is to replace outgoing President Koroma, who was elected in 2007 and reelected in 2012.

In the assembly elections, concurrent with the first round of the presidential election, only 90 of the 132 constituencies have been declared so far. (There are also 12 seats reserved for tribal chiefs.) The SLPP has won 47 seats to the APS’s 32. The Coalition for Change has eight, despite its presidential candidate having placed fourth with only 3.5% of the vote. Obviously the Coalition for Change has a regional base, and parties with regional strength can win under FPTP despite having a low nationwide vote total. (National vote totals for assembly are not yet available.) The party of the third-place presidential candidate, who won 6.9%, is called the National Grand Coalition, but evidently it is not. On the other hand, it also is apparently not regional, having won no assembly seats (at least among those declared).

The assembly has been increased in size from the last election, when there were 112 elected seats. This remains slightly undersized for a country with a population around seven million. The Cube Root Law would imply an assembly of around 192.

As for the assembly party system, the current assembly size, S=132 (ignoring the indirectly elected chiefs), and the use of FPTP (M=1) implies an effective number of seat-winning parties, NS=(MS)1/6=2.26. On currently declared seats, we have NS=2.45 (counting each of three independents elected thus far as a “party”). That is only a very minor deviation from expectation.

The combination of FPTP for assembly and a two-round presidential election might be expected to inflate NS due to the expected (and observed) proliferation of presidential candidates seeking votes in the first round. At least it would be so expected if one believes in coattail effects. There were sixteen presidential candidates contesting the first round, and seventeen parties with assembly candidates in at least some districts.

While the effect of the first-round threshold of 55% is not clear, we might expect it to enhance fragmenting effects, relative to a standard majority runoff. Candidates who are unlikely to win might enter anyway, hoping to deny even a strong leading candidate an outright win. Given that an outright win is more difficult in Sierra Leone than in other two-round systems, the effect might be to enhance first-round fragmentation. Under a “coattails” expectation, that fragmentation would carry over into the assembly elections, even with the use of FPTP for those elections, held concurrent with the first round of the presidential contest.

In Votes from Seats, Taagepera and I express some skepticism about coattail effects, at least in terms of their impact on the effective number of parties. In fact, we go so far as to claim that one can deduce the effective number of presidential candidates (NP) from the assembly electoral system. A more direct logical expectation, developed in the book, goes from the assembly voting party system to NP; to the extent that the voting fragmentation (measured by the effective number of vote-earning parties, NV) is over-fragmented, relative to the electoral system expectation, then NP will be inflated as well.

Sierra Leone is thus a good test case for the logical models of Votes from Seats. First of all, it has changed its assembly size twice now, while retaining FPTP. Second, as noted already, it combines the FPTP assembly electoral system with a two-round presidential formula that might tend to increase fragmentation of the presidential contest. If it does so, it may also tend to increase NS and NV, if coattails explain assembly party-system fragmentation. In a table below are the results, showing all three actually observed effective numbers (NSNVNP), where available, and the expected values. The expectations are derived from the seat product (MS) in the case of NS, but for NV, we should use the derivation from observed NS, because if the latter is over expectation, for sure NV will be, too. For NP, the table reports the expectation from NV, which is the more direct route. Again, if NV, is higher than expected (perhaps because so is NS), then NP will be, as well. However, we can also compare the institutionally grounded expectation, derived from MS only.

What we see is that NV was far “too high” in the initial election under the current constitution, given the quite low assembly size. So was NP, and thus it looks like a “win” for the coattails expectation, perhaps because as an initial election before the civil war (starting 1991) was fully settled, many candidates may have entered unsure of who would be viable. The 2002 election, following the settlement of the war, also looks like a case of coattails, as the winner easily dominated the field, leading to very low values of all three effective numbers.

Nonetheless, on average, the institutionally derived expectations perform well. Even with the first election being well off the expectation (and the second, too, albeit less so and in the opposite direction), overall, the ratio of observed NS to actual has been only a little above 1.00; the ratio of expected to observed is 1.153, shown in the bottom line. (If we ignore the anomalously fragmented 1996 election, the mean NS is 2.175, or slightly below the expectation from the assembly sizes used in 2002-2018.)

Given actual NS, the observed NV has been almost exactly as expected, on average, with a ratio of 1.025. And while the slight over-fragmentation of the average assembly election result in Sierra Leone gets magnified when we look at expected NP from MS (i.e., from the assembly electoral system only, for which the ratio is 1.225), the expected NP from observed NV is not too far off, with a ratio of 1.16. Note that the ratio for NP from observed NV is almost the same as the ratio for NS from the assembly seat product.

Thus, even with a presidential electoral formula (super-majority runoff) that theoretically promotes more fragmentation than the assembly electoral system (FPTP), there is scant evidence–beyond 1996–that we are unable to predict the assembly party system from the assembly electoral system. There is also scant evidence that we can’t predict voting fragmentation for both assembly and presidency from the assembly party system. The small over-fragmentation of the assembly party system, on average, gets carried through to the other measures. This over-fragmentation might be due to the fragmenting incentives of the presidential electoral formula, but only in 1996 is the evidence for such an explanation, based on candidate entry and their coattails, compelling. Otherwise, it seems the assembly seat product allows us to get a pretty good handle on the output indices of Sierra Leone’s elections.

The seat product model, based on the assembly electoral system, performs well, even in a new post-war democracy like Sierra Leone, and even given the country’s somewhat unusual combination of institutions.

The US Supreme Court gerrymandering case

I do not have time to dissect the arguments before the US Supreme Court in the case concerning the permissibility of the partisan gerrymander in Wisconsin. It clearly is a case of great importance to issues we care about at this blog. So, feel free to discuss here.

I highly recommend two pieces by Michael Latner:

Sociological Gobbledygook or Scientific Standard? Why Judging Gerrymandering is Hard (4 OCt.)

Can Science (and The Supreme Court) End Partisan Gerrymandering and Save the Republic? Three Scenarios (2 Oct.)