Probability Distributions

In the last post, we showed some early probability distributions that model the number of seats each party would win, and the associated probabilities. Probability distributions are perhaps not polite dinner party conversation topics (K and I have made this mistake many a time) but they are hugely important. Its a neat way to represent the degree of uncertainty about the outcome of certain events. The only thing we know for sure re how many seats the ALP will win:

  1. They will definitely win between 0 and 150 seats.
  2. The probability of them winning exactly 0 seats, 1 seat, 2 seats etc must be between 0 and 1.
  3. If we add up all the probabilities for winning each seat, it would add up to 1.

I thought it might be relevant to point a few things out about the probability distribution we showed in the previous blog.

  1. We’ve obviously put two probability distributions into the same chart. In future, we’ll likely separate them out in case there is any overlap which makes it hard to see stuff.
  2. The shape of the distributions look bell shaped (ie. normally distributed). This is called a Poisson-Binomial distribution, and is well-approximated by a normal distribution in some cases.

Only bell we could find

We hope to dive into more analysis of the politics in future blog posts instead of making you go through our version of stats 101!

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One thought on “Probability Distributions

  1. One thing you could try is to present the charts as line charts rather than bar charts. That would keep them both on the same set of axes.

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