Because of its small population—despite being the largest state in area—Alaska gets to elect only one member of the U.S. House of Representatives. Until last year it used the traditional system: a separate primary for each party chooses one finalist apiece by First Past the Post (FPtP), and then those finalists compete head-to-head in the general election. Fifty-one years ago Alaska elected a Democrat by that method. After that, it never again elected a Democrat…until last year. Not coincidentally, last year was the first time Alaska used their quirky new hybrid voting system.

I started to write my own explanation of this system, but soon decided to quote from CNN’s explanation instead:

The special election for Alaska’s lone House seat is the first time the new system is in use.

Elections in Alaska now start with an “open” primary, in which candidates of all parties compete and all voters are allowed to participate, casting their ballots for the one contender they prefer. The top four vote-getters, regardless of party, advance to the general election.

Then, in the general election, instead of just voting for one of the top four candidates, voters rank their preferences in order. They are allowed to rank candidates one through four, but are not required to do so—voters could instead choose only to rank their preferred candidate, or only rank their top two.

If no candidate receives more than 50% of the first-place votes, then the ranked-choice system is used to determine the winner.

If you’re unfamiliar with how votes are counted in a ranked-choice system, read Wikipedia’s exceptionally clear account of the method. You may want to note that it’s the system that Cambridge, Massachusetts, has been using for decades to elect its city council.

So what does math have to do with it? And why did Alaska elect a Democrat—who is not only a Democrat but also an indigenous woman? For one answer, let’s turn to Robert Reich:

If this doesn’t look like math, you might just be thinking too narrowly about what math is—perhaps as comprising algebra, geometry, trigonometry, and calculus, perhaps in that order. And then…“What comes after calculus?” more than one student has asked me. But there are more than four areas of study that are part of mathematics, and there’s more than one path through them. Try the jumble of topics that come under the umbrella of discrete math, or chaos theory, or social choice theory, or of course number theory or game theory. And often logic is part of mathematics—or vice versa to some. And there’s graph theory, which has nothing whatever to do with you probably think a graph is.

OK, I’ll stop there. There’s no room in this post to show you why RCV is part of mathematics, but you can look into it. Trust but verify, as someone said. As for why it would be good for Massachusetts in particular, that will wait for another post.

Categories: Life, Math