Discovering distributions

Distributions are often discussed when statistics come up; they have even been mentioned earlier in this book. The question is, what are they? A statistics class will tell you something like the following: a distribution is a function that describes a line that depicts the probabilities of any theoretical outcome that occurs, based on the evidence of a study. Is this easily understood and actionable information? Not really.

Effectively, you can think of a distribution as a model of historical data. It tells you how likely a specific value is when compared to everything you have collected before. This has all kinds of uses. You can predict the probability that a new entry will be a specific value, or in a range of values. You can take a value and see how it compares to the rest of your information. It even turns out that the shape of your distribution can tell you all kinds of things. Additionally, several statistical methods require a specific distribution...