Wrong Priors?

arXiv:0709.1067v1 : Wrong Priors (Carlos C. Rodriguez)

This came through today on astro-ph, suggesting that we could be choosing priors better than we do, and in fact that we generally do a very bad job of it. I have been brought up to believe that, like points in Whose Line Is It Anyway, priors don’t matter (unless you have very little data), so I am somewhat confused. What is going on here?

One Comment
  1. Brendon J. Brewer:

    Hi,

    This is a very old post, but I just figured out what’s going on. Carlos got wrong answers in his MCMC because with the diffuse prior there is a massive phase transition and you need Nested Sampling. There is nothing “wrong” about the diffuse prior in this problem.

    Cheers,
    Brendon

    06-01-2012, 2:47 pm
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