What is voting?
Voting is a poll, but with teeth. Not only does preference information get collected from people, there is an automatic method of turning that information into an outcome. Voting is a form of group decision-making.
This feels immediately political, but it is not necessarily. Book clubs might vote on what book to read next. A group of friends might vote on what movie to see together. In a bake-off, people will vote for their favotite dish, with the winner getting a prize. Combining the poll with the outcome makes this a vote. A motion gets passed, an office gets filled, a movie gets watched, or a baker gets a prize.
A voting method needs two things:
- A ballot – what information can voters provide?
- An algorithm – how to combine all the ballots and find a winner.
We usually assume that voting is egalitarian. All voters have an equal voice. That does not mean “one person, one vote.” It means “one person, one ballot.”
Most of the voting methods I’m writing about here are single-winner methods. But there are many occasions where a multi-winner method is needed. So yes, that’s a thing. I have questions, some ideas, and never enough time.
Plurality
Plurality voting
Plurality voting is the most common voting system used today. I’ll explain it here, but you already know how it works. You might not have a name for it yet. I’m calling this Plurality, but other names are used such as first-past-the-post.
In Plurality voting, voters mark one candidate on their ballot. Once all ballots are collected, counters add up the numbers of ballots that “vote for” each candidate. The candidate with the most votes wins the election.