It does when you describe it to them and convince or force them to use it, e.g. by removing their ability to score the candidate on a scale.
And it does because you are part of the electorate, situated the same as the others, so the strategy you devise should be the one that yields the result you want given that similarly situated people will reach the same conclusion:
https://en.wikipedia.org/wiki/Superrationality
Special note for the critics of superrationality: Your vote isn't going to change the outcome, so according to classical game theory you should stay home instead of wasting your time doing something that doesn't matter. Therefore, voting at all is an exercise of superrationality. If you're not willing to use it in your voting strategy then you shouldn't use it in deciding whether to vote to begin with and so you should either use a superrational voting strategy or you should stay home.
> If a voter values preventing the worst case over achieving the best case, then the optimal strategy is to assign maximum scores to every candidate except the worst case.
You're not thinking probabilistically.
Suppose there are two plausible final election outcomes where your vote matters:
Option 1, candidate A is at 4.99/10, candidate B is at 5/10, candidate C is at 4/10.
Option 2, candidate A is at 4/10, candidate B is at 4.99/10, candidate C is at 5/10.
If it's option 1 and you assigned 10/10 to candidate B, your preferred candidate loses. If it's option 2 your preferred candidate can't win and if you assign 1/10 to candidate B, your least preferred candidate wins.
But if you assign 10/10 to candidate A and 5/10 to candidate B then in option 1 that could still be enough to see candidate A win, and in option 2 it could still be enough to see candidate C lose.
Moreover, the score allows you to express how concerned you are about each outcome. If you're pretty okay with candidate B but have a moderate preference for candidate A then you can give candidate B 7/10. If candidate B is almost as bad as candidate C you can give candidate B 3/10. It allows you to hedge: How much advantage for candidate A are you willing to give up to reduce the chances of candidate C? You seem to be assuming that the only possible answers are "all of it" or "none of it", but there are other options.
> Expressing that preference directly reduces the likelihood of each such voter's preferred outcome, even if a single voter does it. It affects the chance of the worst-case outcome only if voters on both sides of the A/B division do it.
If affects the chance of the worst-case outcome in all cases because it increases candidate C's chance against candidate B, and you don't know what the other voters are going to do. If candidate A has less support than expected due to inaccurate polling then it turns into a race between B and C regardless of whether B's supporters give A 1/10 or 5.5/10. Meanwhile you assigning a lower score to B is reducing B's chances against C regardless of why the race turns out to be between B and C.
> This is exactly a prisoner's dilemma.
No it isn't. In a prisoner's dilemma, defection is to your advantage regardless of what the other person does. In this case, if the other party defects -- and sometimes even if they don't -- then your defection harms you, because their defection (or something else) put candidate A behind candidate C. Then it's not clear if your support for candidate A will allow them to defeat candidate C, but if it isn't, your defection in assigning the lowest possible score to candidate B would cause candidate C to defeat candidate B, which is to your own disadvantage.
> Since you don't know that, your choice of an intermediate score is a statistical expression.
It has less information content. If you roll a D10 and then assign 10/10 to candidate B if it's above a 6 and 1/10 if it isn't, the voting system only gets a single bit of information from you, whereas assigning the equivalent score gives it >3 bits of information. That only matters if the election is very close, but it always only matters if the election is very close.
In 2024 there were dozens of state legislative races decided by fewer than 100 votes:
https://ballotpedia.org/Election_results,_2024:_State_legisl...