[EM] Continuous bias

[Kristofer Munsterhjelm]

Juho Laatu wrote:
> The final of the Eurovision Song Contest of this year was held last
> saturday. In the vote all countries give points to the songs of all
> other countries (that made it to the final). The voting traditions
> are a bit biased. Countries tend to give high points to their
> neighbours or otherwise similar countries. Countries are not allowed
> to vote for themselves, but minorities living or working in some
> country may have considerable impact since they may have sympathies
> also towards some other country. All this means that in addition to
> voting for good songs people vote also for their best friends.
> Eurovision Song Contest is a friendly competition though, and a major
> carnival, and people don't worry too much about this kind of (well
> known) voting patterns. Maybe they are just part of the fun and even
> one essential part of the competition. But as a person interested in
> voting I started wondering if this kind of voting patterns could be
> fixed or eliminated.
> 
(...)
> Would this approach maybe be useful and practical somewhere? What
> other approaches there are to eliminate this kind of systematical
> bias?

There's a problem with this sort of blind compensation, because the 
method itself can't know whether the bias is because a country is 
consistently good or because the other countries consistently favor that 
country.

Say, for instance, that country X somehow gets very good at making 
Eurovision songs, so it wins a lot more often than would be expected by 
chance. Then your compensation scheme would make it harder for X to win; 
X is punished, ratchet effect style, for being good. It gets even more 
blurry when you consider that the countries reward each other according 
to "popularity" - perhaps the people of the Eastern European countries 
like the kind of music they themselves make, for instance, so that the 
"bias" is indirect rather than direct?

I think the proper way to do this, if getting rid of bias were to be 
important, would be to make a video (or audio) recording of each 
country's song and then play it without saying what country it is. The 
countries then rate based on that alone, and the country names are 
revealed afterwards. However, there are many ways to "smuggle" 
information through audio and particularly video, so it would only 
weaken the effect. Besides, it would affect the circus aspect of the 
Eurovision Song Contest, and would be nearly impossible since the ESC 
has multiple rounds.

Alternatively, one could use strategy-resistant methods: median ratings 
if cardinal, or something like the "IRV until there's a CW" method if 
ordinal, so that the actual effect of this kind of bias is weakened 
further. Borda is very manipulable, and I expect the Eurovision variant 
isn't far off Borda level, either.

(I can't really see Eurovision doing the Condorcet-IRV method though: 
"Let's see if there's a pairwise champion among those who remain! No? Oh 
well, too bad, Germany: you're out!". :p)