downdate_beta_binomial

function downdate_beta_binomial(x:Integer, n:Integer, α':Real, β':Real) -> (Real, Real)

Downdate the parameters of a Beta distribution with a Binomial likelihood.

  • x: The variate.
  • n: Number of trials.
  • α': Posterior first shape.
  • β': Posterior second shape.

Returns: the prior hyperparameters α and β.