When a model estimates unknown parameters from observed data, a single best-fit value can hide uncertainty. Posterior probability describes the conditional distribution of those parameters given the observed variables and a prior probability distribution. section 2.3.4
Bayesian estimation treats parameters as random variables, specifies prior beliefs through hyperparameters, and updates inference using the observed data. If latent variables are present, inference can target their joint distribution with the parameters. section 2.3.4
The posterior distribution supports several practical uses:
- Represent uncertainty about parameter values instead of returning only a point estimate. section 2.3.4
- Carry parameter uncertainty into predictions and other inferences. section 2.3.4
- Represent inference results with samples or parameter values drawn from the distribution. section 2.3.4







