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.

The winner is chosen using a Borda like method. Each country gives points to 10 
songs that they consider best. Those songs are given 12, 10, 8, 7, 6, 5, 4, 3, 
2 and 1 points. In the final there have been 25 or 24 songs, so all the 
remaining songs will get 0 points. Then the points are summed up and the 
song/country with most points wins.

I compared the number of points that each country gave to each other country to 
the average number of points that that country got. After checking few previous 
years the patterns were quite obvious. The basic fix to the problem could be 
such that if country A gives on average k times as much points to country B 
than others do, then the points given by country A to country B in the next 
election will be divided by n. One could make this function also softer in the 
sense that one would not reduce the points that much, or one would put higher 
weight on the few last years only, or giving low points once would be 
considered a proof that the pattern is not systematic (and that would reduce 
the factor more that giving high points increases it). But I guess the basic 
idea is clear. Systematic positive bias leads (in the next election) to 
reduction in the points that A gives to B. (Negative bias may not be that 
relevant.)

This Eurovision Song Contest vote is a Borda like election, but this approach 
would work as well and better also for Range like elections. One could rig it 
for ranked elections too (e.g. in a pairwise comparison table based Condorcet 
method one vote could add only 1/k votes in the some comparison table entry).

Would this approach maybe be useful and practical somewhere? What other 
approaches there are to eliminate this kind of systematical bias?

Juho



P.S. The highest factors that had lasted systematically for several years were 
somewhat above 10. I.e. some countries gave systematically 10 times as many 
points to some other countries than others did. (Since countries participating 
in the competition and countries that make it to the final are not always the 
same, the results can not be computed for all country pairs for every year. 
Therefore I required some minimum number of entries (possibility of A giving 
points to B) (e.g. 3 or 4) to count the factor for some pair of countries.)







----
Election-Methods mailing list - see http://electorama.com/em for list info

Reply via email to