4 ms·

help me out here, I don't understand how the spoiler effect returns if the third party candidate becomes competitive. Wouldn't that just mean they have a chance

• elihu 5y ago
  That's a pretty good example, because it illustrates a disconnect between how people expect IRV/RCV to work and how it actually works. Biden would be eliminated first, because he had the fewest 1st choice votes in the first round. The Dave Chappelle voters' 2nd choices for Biden don't matter: they're thrown out because Biden was eliminated. So, it comes down to Chappelle with 40% and Trump with 45%. If none of the Biden voters listed Chappelle as their second choice, then Trump wins. If enough voters had Chappelle as their second choice, then Chappelle wins. The lesson from this example is: it's quite possible that your second choices don't matter, because they're eliminated too early. We could come up with other examples that show that it isn't always safe to put your first choice first, either. IRV/RCV is non-monotonic, which means in some cases you can cause a candidate to lose by ranking them higher.