[EM] DH3 "horribly common"?

[Abd ulRahman Lomax]

At 11:59 PM 10/15/2005, Warren Smith wrote:
>--I actually am aware of one case in which DH3 in fact did happen in
>a real vote (which I was involved in) with large ($100,000+) 
>consequences at stake.
>For that story see
>    http://math.temple.edu/~wds/crv/rangeVborda.html
>section 2.

First of all, there seems to have been a combination of idiocies in 
the example on that page. This was not a public election. And the 
voters, indeed, foolishly exaggerated their votes to try to obtain a 
personally desirable outcome, and, indeed, they got a bad outcome. As 
I indicated, if the voters are massively foolish, as they were in 
this case, how can you expect other than a foolish outcome?

By the way, wouldn't Range have produced similar results with similar 
selfish exaggeration?

>  also point out that another example was the world's only Borda 
> government (Kiribati)
>where again such phenomena were immediately observed.

Borda is particularly vulnerable to this problem, but I would think 
Range would be as well. But what do I know? Not much....

>--As far as "horribly common" by that I meant (as I described on the DH3 page
>    http://math.temple.edu/~wds/crv/DH3.html )
>that DH3 occurs whenever there are 3 comparable rival good 
>candidates and a bad one.

The theory here is that voters will rank the bad candidate higher 
than the rival good candidates. And the bad outcomes seen are proof 
that the strategy sucks.

What is needed in a democracy is for voters to *trust* democratic 
process by voting sincerely. If enough voters try to distort the 
system by strategic voting, in order to gain a very short-sighted, 
narrow, and immediate purpose, any system which depends on sincere 
ratings or rankings is going to be in trouble.

>And since DH3 leads to the worst candidate winning (in the 3 rivals 
>+ dark horse
>scenario) it is also "horribly" i.e. maximally, serious.

Perhaps. Those voters get what they deserve. Because they lied in the 
voting booth, they cannot complain that the candidate they voted for, 
over two candidates that would actually have been acceptable to them, 
actually won.

[...]
>So MDDA and DMC and many other methods are kind of like dark pools 
>of ignorance
>in which monsters may lurk.  It is worrying to base your government 
>on such a thing.

Range voting has not, to my knowledge, ever been used in public 
elections. It is used in systems where experts are ranking 
performances or proposals. And in the latter case, I recently saw a 
situation where a rating was distorted badly by an outlier, that is, 
by someone who consistently rated the proposal (for a charter school) 
lower than everyone else, with unused ranks in between.

In any case, Range in public elections is indeed an unknown. I'd be 
much more comfortable seeing it used in party polls, rather than 
primaries, per se, if the primaries rigidly determine the candidates.