[EM] Condorcet question - why not bullet vote

[Dave Ketchum]

So, why bother to vote for one or more?
      There are two leaders, and I have a preference (or three of  
which I prefer one or two)..
      I see clones so, if I like what they are, I should vote for all  
of them.
      I like what I hear of a candidate, so hope to attract more like  
this one, even if they are not getting many votes this time.

Therefore:
      Among the leaders it matters, so you vote if you care.
      Among the also-rans it does not matter, so you vote if you care.
      Among those who might be on the edge of a significant vote count  
it only matters if the one you consider bullet voting, and the one you  
are considering as an option, are both on the edge such that you could  
regret whatever you do, that it is time to worry.  So vote if you  
care, for voting can either help or hurt.

The studying here mostly makes headaches.

Dave Ketchum

On Jun 16, 2010, at 2:20 PM, Kevin Venzke wrote:
> Hi Peter,
>
> My quick responses to this:
>
> --- En date de : Mer 16.6.10, Peter Zbornik <pzbornik at gmail.com> a  
> écrit :
>> I got a second question from one of our members (actually the same  
>> guy
>> which asked for the first time):
>> If I just bullet vote in a Condorcet election, then I increase the
> chances
>> of my candidate being elected.
>> If I have a second or third option, the chances of my prefered  
>> candidate
>> to win is lowered.
>
> None of this is guaranteed. Actually listing additional preferences  
> can
> also help a preferred candidate.
>
>> Q: In this case why should any voter not bullet-vote?
>
> You should not bullet vote if the possible use of voting for a second
> preference outweighs the likelihood that the second preference will  
> hurt
> your first preference.
>
> It is not obvious that a voter should be trying to support his  
> favorite
> candidate to the exclusion of everything else. He should be trying to
> get the best result possible on average.
>
>> My argument starts:
>> If I vote for a candidate who has >50% of the votes, then it does not
>> matter if there is a second or third choice.
>> If my prefered candidate A gets <50%  of the votes, then it makes  
>> sense
>> to support a second choice candidate B.
>> However if the supporters of B only bullet vote, then maybe B's
>> supporters get an advantage over A?
>
> Yes, that can happen. But it doesn't follow from this, that everybody
> should bullet-vote. If A and B are similar candidates then all of  
> these
> voters benefit from the A>B votes even though the B voters only voted
> B and denied A chance to win. Most likely if the A voters bullet-voted
> also, then some other candidate would win.
>
>> ... at this point I realize, that I don't know enough about Condorcet
>> and/or Schulze to answer the question.
>>
>> Why is it not rational to bullet vote in a Condorcet election if  
>> you are
>> allowed not to rank some candidates?
>
> It could be rational in some cases, but it is not rational in  
> general. In
> general it makes sense to express your preferences.
>
> Kevin Venzke