Index: wiki/eggref/4/statistics
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The library provides a number of formulae and methods taken from the book "Fundamentals of Biostatistics" by Bernard Rosner (5th edition).
=== Binomial Distribution

The [[http://en.wikipedia.org/wiki/Binomial_distributionBinomial distribution]] is what you get from counting discrete events in a series of trials, each of which events has a probability p of producing a positive outcome. An example would be tossing a coin {{n}} times: the probability of a head is {{p}}, and the distribution gives the expected number of heads in the {{n}} trials.
+=== Statistical Distributions
+
+To use this library, you need to understand the underlying statistics. In brief:
+
+The [[http://en.wikipedia.org/wiki/Binomial_distributionBinomial distribution]] is used when counting discrete events in a series of trials, each of which events has a probability p of producing a positive outcome. An example would be tossing a coin {{n}} times: the probability of a head is {{p}}, and the distribution gives the expected number of heads in the {{n}} trials.
+
+The [[http://en.wikipedia.org/wiki/Poisson_distributionPoisson distribution]] is used to count discrete events which occur with a known average rate. A typical example is the decay of radioactive elements.
+
+The [[http://en.wikipedia.org/wiki/Normal_distributionNormal distribution]] is used for realvalued events which cluster around a specific mean with a symmetric variance. A typical example would be the distribution of people's heights.
== Provided Functions