Talk:Conjugate prior/Comments

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Please add useful comments here--Cronholm144 09:02, 24 May 2007 (UTC)

1. There should be a note that the gamma priors are parameterized by rate, not by scale (at least in the handful that I checked).

2. The fourth reference should be removed because of serious errors; it is a reference, and the errors are in the material for which is it supposed to be a reference.

Fink, D. 1995 A Compendium of Conjugate Priors. , http://www.people.cornell.edu/pages/df36/CONJINTRnew%20TEX.pdf

At least two of the posterior hyperparameters in that reference are incorrect

The first, p 11, is for a gamma prior for the rate of a Poisson. The prior is parameterized with beta as a scale (eqn 31), but the posterior scale hyperparameter beta is given as beta/(1+n), which is incorrect. It should be beta/(1 + beta * N).

The second, page 18, is for a gamma prior for the precision of a normal. The prior is parameterized with beta as scale hyperparameter (eqn 62), but the posterior scale hyperparameter beta is given as beta + n, (eqn 63) which is correct when beta is rate, not scale.

Dstivers 21:57, 25 September 2007 (UTC)