[EM] Top Two Runoff versus Instant Top To Runoff

[Kristofer Munsterhjelm]

James Gilmour wrote:
> Kristofer Munsterhjelm  > Sent: Sunday, November 23, 2008 4:11 PM
>> I'm not Kevin, but I think I can comment. In any method that's [some 
>> base method] + runoff, where the runoff candidates are picked from the 
>> social ordering of the base method, the existence of the second round 
>> would increase the incentive to strategize.
> 
> So what happened to the incentive to strategize in the first round of
> the 2002 French Presidential election?

> First Round Results	
> Jacques Chirac  Rally for France (RPF) 19.83% 
> Jean-Marie Le Pen  National Front (FN)  16.91% 
> Lionel Jospin  Socialist Party (PS) 16.14% 
> François Bayrou Union for French Democracy (UDF)   6.84% 
> Arlette Laguiller  Workers' Struggle (LO) 5.73% 
> Jean-Pierre Chevènement  Citizens' Movement (MC) 5.33% 
> Noël Mamère  Greens (Vert) 5.24% 
> Olivier Besancenot  Revolutionary Communist League (LCR) 4.26% 
> Jean Saint-Josse  Hunting, Fishing, Nature and Traditions (CPNT) 4.25% 
> Alain Madelin  Liberal Democracy (DL) 3.92% 
> Robert Hue  Communist Party (PCF) 3.38% 
> Bruno Mégret  National Republican Movement (MNR) 2.35% 
> Christiane Taubira  Radical Left Party 2.32% 
> Corinne Lepage  Citizenship, Action, Participation Movement (MCAP) 1.88% 
> Christine Boutin  Social Republican Forum (FRS) 1.19% 
> Daniel Gluckstein  Workers' Party (PT) 0.47% 
> ELECTORATE: 40,320,334  
> TURNOUT: 29,149,143  

There was no strategizing (that I can see), and the left-leaning parties 
split the vote. TTR isn't perfect, I never claimed that.

When I wrote my reply, I was referring to the kind of strategy that 
could backfire on the voters if it's taken too far - something like 
burial in Condorcet. That is the sort of strategy you wouldn't want, and 
I said that I thought runoff systems would have more of them in the 
first round because the stakes would be lower. On the other hand, the 
second round, or last if there are more than two, must be (and is) honest.

I am a bit surprised that nobody were doing any sort of pushover 
strategy here, but then, they might; there's too little information to 
say and I don't know the general French opinion at the time.

> The second round of this TTRO election was a choice between one
> candidate from the centre-right and one candidate from the extreme
> right, despite two-thirds of the voters supporting candidates from
> the  left.
> Jacques Chirac received 25,316,647 votes (82.14%) and Jean-Marie Le
> Pen received 5,502,314 (17.85%). Around 4% of votes were spoilt
> in protest and 20% of the electorate did not vote.
> 
> I am convinced that had this been an exhaustive ballot (multi-round
> run-off), IRV or Condorcet election, the result would have been
> quite different. Certainly the final "top two" choice would have been
> very different.

Plurality is a really bad method. TTR is better, but TTR is ultimately 
based on Plurality. Condorcet + top two, or Approval + top two, or 
something like that, would have provided better results as well, I 
think; the question is whether it'd be sufficiently better than the 
method without top two that it'd be worth it.

If you're referring to how I've earlier supported TTR above IRV, well, 
in this case, IRV might have given the right result. But then again, the 
dynamics could have been different. Would there have been that many 
parties had all previous elections been IRV and not TTR?