How to do democracy — Voting Systems

If you like democracy, that’s great, go you! You’ll probably find this article interesting. Democracy is a political system whereby the will of the people is reflected in the decisions of their government. A big part of doing democracy is voting, where the people pick representatives who they think (or hope) will act in their best interests.

It sounds simple, but democracy gets complicated very quickly. For instance, if you’re a representative, does acting in the best interest of your constituents involve doing what they want you to do? Or is it what you think is best, since they presumably elected you to exercise your judgement? Or perhaps what your party thinks is best, because that’s the platform you were elected on? Maybe it’s something else, maybe you should compromise and negotiate with other representatives, even if nobody is 100% happy, because compromise might yield the best possible outcome in your particular situation.

There are many, many issues, but this article is going to cover voting systems, that is, how we elect our representatives in the first place. There are many democracies over the world which use a range of different systems. We’re going to focus on three main ones and show you the very different results that can come about from the same preferences in the same population.

We’re using data from the 2010 Australian election, and here’s why:

• The election was a close one — no party won an outright majority in the Australian House of Representatives…