If I understand the meaning of the original example correctly, the answer is Asset voting.
Give every voter 100 points. By the conditions given, both the A and B voters think C is 80% as good as their true favorite, so give 5/9 of their points to their favorite and 4/9 to C. A's total is 55 x 5/9 = 275/9 B's total is 45 x 5/9 = 225/9 C's total is 55 x 4/9 + 45 x 4/9 = 100 x 4/9 = 400/9 so C wins. ---- Election-Methods mailing list - see http://electorama.com/em for list info