Truncation with Condorcet

[David Marsay]

Sorry for the tardy response, but I did enjoy my vacation.

My interpretation (version?) of Condorcet is that one should count 
the 'plurality': the votes for minus the votes against. Hence 
Blake's randomising strategy should not change the result. In his 
example, C beats B by 6 votes in both cases.

Blake's method could 'backfire' if the votes do not exactly match. 

Cheers.

> Date:          Fri, 07 Aug 1998 23:28:54 -0700
> From:          "Blake Cretney" <bcretney at my-dejanews.com>

> 
> On Fri, 7 Aug 1998 04:00:54    Mike Ositoff wrote:
> >On Thu, 6 Aug 1998, Blake Cretney wrote:
> >
> >> Why would anyone ever sincerely truncate a ballot under
> >> Condorcet?  <SNIP> 
> What about this example?
> 
> 24 A B C \  Sincere preference A > B=C
> 24 A C B /
> 23 B A C
> 29 C B A
> 
> The A 1st voters took my advice and marked the other 
> candidates randomly instead of truncating.  They came 
> out even.
> 
>        A    B    C
>   A    X    48   71
>   B    52   X    47
>   C    29   53   X
> 
> Max loss
>        52   53   71
> A wins
> 
> Now here's what happens if they vote sincerely and 
> truncate
> 
> 48 A
> 23 B A C
> 29 C B A
>        A    B    C
>   A    X    48   71
>   B    52   X    23
>   C    29   29   X
> 
> Max loss
>        52   48   71
> B wins
> 
> So unless I've made some kind of error here, it can 
> sometimes hurt to use truncation instead of my random 
> fill strategy.
> 
> The question is, is there any situation where this can 
> backfire?  That would give a reason not to always use 
> my random fill strategy.
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Sorry folks, but apparently I have to do this. :-(
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