2007-04-01

Bayesian methods in animal breeding and theory

I have finally read the seminal paper by Gianola and Fernando (1986). I had it in my pile of must read papers for some time now. I guess around two years. Phuh! I am glad I read it since it is nice to see how thing conceptually have not changed a lot from that time. It is 20 year from then, but you can still find the same stuff is in the papers today. The only difference is that now problems are tackled with use of MCMC machinery, while the concept is the same. Is this a sign of ...? I also liked the paper since a lot of issues that you find in many different places are in one place. I would rate is as a must read paper for anyone working in field of animal breeding. I wonder if it can be recommended as an introductory paper to Bayesian way for animal breeding problems. I had some experience with Bayesian approach and have read a lot of literature on this topic so my impressimon might be distorted. Anyway, I found it nice to refresh the setup and to take a journey from Bayes theorem, posteriors, priors, likelihood, sequential inference of breeding values, sample data domination, Bayesian asymptotic theory, integration of nuisance parameters, a pinch of Jeffrey's priors, inference of breeding values with informative priors, a touch to Henderson's mixed model equations when priors are uniformative and variance components known, biased but better (in the sense of mean-square error) estimators, selection and assortative mating, Bayesian view of selection index (best linear predictor) and best linear unbiased predictor, nonlinear merit functions, nonlinear models, Bayesian estimation of (genetic) parameters - variances. Oddly, paper finishes with "a cut" - no real end. Weird. Blasco is more recent example of such a paper. It covers quite a lot of topics as Gianola and Fernando (1986) - I told you thing are repeating, but also adding comparison with frequentist/likelihood approach and is writen in a way that also people that are not everyday into the statistics.

Blasco, A. (2001) The {Bayesian} controversy in animal breeding. Journal of Animal Science. 79(8):2023--2046 http://jas.fass.org/cgi/reprint/79/8/2023

Gianola, D. and Fernando, R. L. (1986) Bayesian methods in animal breeding and theory. Journal of Animal Science, 63:217-244

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