parameterization of inverse gamma prior in the Stata bayes platform

[Paul Rathouz]

Hi – The -bayes- platform in Stata used the inverse gamma (alpha, beta) [alpha=shape, beta=scale] prior for variance parameters. I have searched the documentation, but remain confused about the second parameter. In the Stata parameterization:

• If X~InverseGamma(alpha,beta), does this mean that X~Gamma with shape alpha and scale beta?
• Or, does it mean that X~Gamma with shape alpha and *rate* beta? I.e., scale (1/beta)?

See: https://en.wikipedia.org/wiki/Invers...ion#Properties .

Thank you. – Paul