A Bayesian approach to geographical genetics

What in the FST is going on?

What is FST?

Why be Bayesian?

You are here

Hillis, D. M., D. Zwickl, R. Gutell. University of Texas

Erickson, R. O. Annals of the Missouri Botanical Garden 32:413-460; 1945

•Genetic drift

Wright. Genetics 16:97-159;1931.

•Genetic drift•Mutation

Wright. Genetics 16:97-159;1931.

•Genetic drift•Mutation•Migration

Wright. Genetics 16:97-159;1931.

•Genetic drift:•Mutation:•Migration:

Evolutionary process parameters• Determine characteristics of

the evolutionary process

Variance of allele frequencies among populations

Statistical parameters• Determine

statistical distributions

Method of moments• Calculate expectations of

sample statistics• Equate parameters to

expectations• Solve linear equations

Statistical parameters• Determine

statistical distributionsBayesian method

Statistical parameters• Determine

statistical distributionsMethod of moments and

Bayesian method estimate the same parameters

?

This formulation – Wright

(nearly) equivalent formulation using identity by descent – Malécot

Statistical parameters• Determine

statistical distributionsMethod of moments and

Bayesian method estimate the same parameters

Why be Bayesian?

Formal models clarify thinking

Flexible models encourage exploration

Guo et al. Journal of the American Statistical Association 164:142-154; 2009.

Start with an idea (the prior)

Start with an idea (the prior)

Collect some data (the likelihood)

Start with an idea (the prior)

Collect some data (the likelihood)

Reach a conclusion (the posterior)