## Dirichlet Nucleotide Frequency Prior applet

The Dirichlet distribution is normally used to specify the prior distribution for equilibrium base frequencies in Bayesian phylogenetics. Unfortunately, 4 dimensions are required to plot the probability density, so I’ve resorted to showing you samples from the distribution instead plotted using a barycentric coordinate system.

Drag right-to-left (or left-to-right) with mouse to rotate view. Use controls below plot to change sampling distribution. Relative distance from vertex A, for example, is proportional to nucleotide frequency of A.

## Acknowledgements

This applet makes use of d3js and Erik Bernhardsson’s very useful D3-3D code. Please see the GitHub site for details about licensing of other libraries that may have been used in the source code for this applet.

## Licence

Creative Commons Attribution 4.0 International. License (CC BY 4.0). To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ or send a letter to Creative Commons, 559 Nathan Abbott Way, Stanford, California 94305, USA.