I am going to do this one in a Q&A format, for questions of my choosing.
Does voting matter in the short term?
It depends on how you look at it. In general, the effect of a vote is inversely proportional to the size of the voting pool. A rational agent would weigh the potential impact of their vote against the cost of voting (getting up, walking/driving to the precincts, etc.) Most of the time, the costs probably outweigh the impact, and thus it’s not worth voting. Now, you might argue that democracy wouldn’t work if everybody did that, but it is fallacious to argue under the assumption that other people follow the same train of thought that we do: they do not, and it is fairly clear that humans in general are not rational agents. Furthermore, nobody argues this on a whim an hour before voting – if the estimated voter turnout is 50% a week before the election, it won’t fall to 10% overnight, and if it does, a rational agent will remember this and will try to take advantage of the low turnout on the next election. Basically, if you know that 80% of people in your county will vote, and that they will massively vote for candidate X, just stay home. Really. Don’t worry, most people won’t change their minds.
But wait! There might be another reason to vote, one that you did not think of:
Does voting matter in the long term?
Yes. Overall, it might matter more than it does in the short term, and it’s a pity people do not see this. In an election, you are focused on its results, and that’s understandable. But that does not mean you cannot look into how your vote might impact future elections. Because let’s face it – an election is not a matter of life or death, and by always looking at the immediate future, you merely ensure mediocrity for the next fifty years.
A vote is mind share. Even though a small upstart party has absolutely no chance of winning the current election, voting for it is not a complete waste, to the extent that it places it on the map. People have a limited attention span: the more major a party is, the more likely it is that people will look at it and consider voting for it. Most will only look at the parties that have a chance of winning, plus maybe one rising party. Some will also look at the one or two next-largest parties, that might be large enough to have some credibility. And then some will look at everything. But in all cases, there is a list of parties or candidate, ordered by how well they did in the last election, and their mind share is roughly proportional to that. By voting for a party, you help them rise in that list.
In other words, imagine that 6% of voters like party X. With strategic voting, it gets, say, 3% of the vote. If no strategic voting occurs at all, it gets 6%. Next election, instead of being 3%, the baseline will be 6%. A higher baseline means that more people will consider it and the party will become significant much faster than it would have otherwise. Indeed, with a 3% baseline, maybe 7% of the voter base will like the party next election. With a 6% baseline, it might be 10%, because more people will pay attention to it.
You see, if you want to change the world, that’s how you do it.
Does the participation rate matter?
No. What matters is that voters are an unbiased sample of the population, with reasonable standard errors. A higher participation rate can reduce variance on the result, but if the sample is biased, that’s not even a good thing. To illustrate, imagine a population where 50% of all people lean left and 50% of them lean right. Now, let’s imagine that for some reason left leaning people are slightly more likely to vote than right leaning people. Therefore, in an election, maybe 90% of lefties will vote, and 80% of righties will vote. The tally will be 53% left, 47% right, and the left will win. Over the course of many elections, the left will almost always win, because there is too little variance for the right to get in even once. Now, if you picture an election where only 5% of lefties vote and 5% of righties vote, the victories will be evenly shared between the two sides, which seems much fairer, despite a measly participation rate.
In fact, an election where, say, one to five percent of the population is chosen strictly at random and forced to vote, would probably be more reliable than the current system. It doesn’t really matter much how many people participate, as long as the result is unbiased.
Should the side with the most votes win?
Counter-intuitively, only most of the time. Current democracies only look at the short term, which induces a temporal imbalance: in a society where 55% of the population is on a side, and 45% is on the other, it seems bizarre that the first side would win all the time, rather than 55% of the time. While there is admittedly much more variance in such a process, picking each side with probability equal to its vote share would lead to more representative governance in general. It also eschews trying to come up with a better voting system: all voting systems work from the flawed premise that one should figure out each result with perfect accuracy, even though in fact such a system will not, on average, do better than a stochastic process (in fact, I would argue that no deterministic voting system has theoretical properties that are as good as a stochastic one when you take temporal bias into account).
The main problem here is that people wouldn’t understand such a system: it is natural for human beings to place very inflated importance in particular results, and to loathe variance. People will get angry losing a game because of luck, even though luck always averages out on the course of many games. Why? Because they want to win every single time they believe they deserve it. Obviously, nobody would want to lose a campaign for congress, senate or even presidency on a die roll. And yet, democracy would probably work better if we did that, if only because it would give minorities a louder voice and push us to try new things once in a while. A deterministic system is consistent, but that only means it is consistently mediocre.
Basically, as far as democracy goes, the accuracy of each individual result seems to be a sacred principle, even though there is no mathematical need to go beyond being unbiased. It is also questionable whether the strategy to always reward the front runner works out for us in the long term. Unfortunately, human nature is such that alternatives are unthinkable.
Who should win if the tally is very close?
Just flip a coin. You know how fickle voters are: when an election is very close, that basically means that the candidate who won today would have lost tomorrow, and the one who would have won tomorrow would have lost the day after that. I know that democracy is based on sacred principles, but in evaluating the merits of a system, you have to look at the results. As I have said, what underpins democracy is the understanding that its results are unbiased on average, not the understanding that they are exact. It’s important for morale to make sure that the ballots are counted properly, but don’t fool yourselves into thinking it really matters if they are. As long as there is no fraud (which would induce a bias towards electing corrupt people, and we definitely don’t want that to happen), it doesn’t matter at all. When an election is extremely close, in general, there is no evidence that either side will do better or worse than the other. Besides misguided rigid principles about how democracy should work, a coin flip would work just fine, perhaps even better, since a fraudulent candidates has an edge under the current system.