Often the prior on <math>\theta</math> depends in turn on other parameters <math>\varphi</math> that are not mentioned in the likelihood. So, the prior <math>p(\theta)</math> must be replaced by a likelihood <math>p(\theta\mid \varphi)</math>, and a prior <math>p(\varphi)</math> on the newly introduced parameters <math>\varphi</math> is required, resulting in a posterior probability | Often the prior on <math>\theta</math> depends in turn on other parameters <math>\varphi</math> that are not mentioned in the likelihood. So, the prior <math>p(\theta)</math> must be replaced by a likelihood <math>p(\theta\mid \varphi)</math>, and a prior <math>p(\varphi)</math> on the newly introduced parameters <math>\varphi</math> is required, resulting in a posterior probability |