---
title: "conjugate prior"
type: concept
related: [Probabilistic Programming, Conjugate Prior]
source: https://www.jemoka.com/posts/kbhconjugate_prior/
confidence: high
status: active
---

A conjugate prior of a certain likelihood function \(p\qty(x | \theta)\) is a type of prior where the posterior distribution&mdash;
\begin{equation} p\qty(\theta | x) \end{equation}
is the same probability family as the prior \(p\qty(\theta)\).
This means that updating is very easy; if we can&rsquo;t do this, probabilistic programming!
