7 ms·

For groups of individuals, it is quite possible https://en.wikipedia.org/wiki/Condorcet_paradox https://en.wikipedia.org/wiki/Condorcet_paradox

• theptip 7y ago
  It's obvious that these cycles can exist when the things referred to have labels like "A, B, C" or "carrot, potato, lettuce", but how often do they occur for political candidates like the ones described above? I'm willing to buy that IRV is objectively not suitable for picking meals, but that in practice it is suitable for picking presidential candidates -- or that it's always inferior. Seems like an empirical question, not a theoretical one.
  • ikiris 7y ago
    Thankfully lots of smart people have written papers about how that's incorrect. They just use generic terms like "A,B,C"
  • amalcon 7y ago
    The wikipedia page includes a cite of such an empirical analysis: https://en.m.wikipedia.org/wiki/Condorcet_paradox#Empirical_studies https://en.m.wikipedia.org/wiki/Condorcet_paradox#Empirical_...
    • theptip 7y ago
      Thanks! I'm just going to quote here because the footnote was interesting: > A summary of 37 individual studies, covering a total of 265 real-world elections, large and small, found 25 instances of a Condorcet paradox, for a total likelihood of 9.4%[14]:325 (and this may be a high estimate, since cases of the paradox are more likely to be reported on than cases without).[13]:47 > 13: ""most election results do not correspond to anything like any of DC, IC, IAC or MC ... empirical studies ... indicate that some of the most common paradoxes are relatively unlikely to be observed in actual elections. ... it is easily concluded that Condorcet’s Paradox should very rarely be observed in any real elections on a small number of candidates with large electorates, as long as voters’ preferences reflect any reasonable degree of group mutual coherence" I think I have to file this one under "it's complicated, must dig more".