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Issue 16: A story of distributions

In this issue, I will talk about different distributions and their use.

TL;DR

  • Binomial distribution presents the number of successes for different random experiments.
  • Beta distribution presents the probability of an event. The result is bounded between 0 and 1.
  • Poisson distribution is helpful when you want to model events that occur during a period of time.
  • Gamma distribution is used to model continuous probability distributions.

Binomial distribution

Discrete or continuous values

Discrete

Example of use

Conversion on a website.

You convert or you don’t. It’s a success or a failure. This is what binomial distribution is about.

Beta distribution

Discrete or continuous values

Continuous

Example of use

Useful to model the prior probability distribution when doing ABTests with binomial distribution. There are two parameters: alpha is the successes, beta is the failures

Poisson distribution

Discrete or continuous values

Discrete

Example of use

Goals during a football match.

The period of time is the match. The number of goals are the events.

Better Know a Distribution: The Poisson Distribution

Gamma distribution

Discrete or continuous values

Continuous

Example of use

Useful to model the prior probability distribution when doing ABTests with binomial distribution. There are two parameters: alpha is the occurrences for a period of time, beta is the number of periods of time.

Thank you for reading. Feel free to contact me on Twitter if you want to discuss that.