frameworkProbability and statistics

Bayesian updating

Update a declared prior distribution with a likelihood generated by observed data.

Working definition

Bayesian inference combines a prior distribution and likelihood to produce a posterior distribution. The result is conditional on the model, prior, data-generating assumptions, and observation process; posterior concentration does not protect against misspecification or leakage.

Notation

p(θ|D) ∝ p(D|θ)p(θ)posterior ∝ likelihood × prior

Assumptions

  • Prior and likelihood are declared before evaluation.
  • The observation model reflects sampling and censoring.
  • Model comparison accounts for complexity.

Invariants

  • The posterior normalizes to one.
  • Sequential updating is coherent for conditionally independent batches.
  • Changing the prior can change sparse-data conclusions.

Reproducible procedure

  • Pre-register parameterization and priors.
  • Compute and diagnose the posterior.
  • Run prior sensitivity and posterior predictive checks.

Error and boundary controls

  • Approximate inference adds computational error.
  • Misspecified likelihoods produce misleading certainty.
  • Selection bias is not removed by Bayes rule.

What this does not establish

Bayesian updating can measure how evidence changes belief under a model; it cannot turn repeated post-hoc astrological correlations into prospective evidence.

Explicit applications

2 cross-domain bridges

Astronomy knowledgephysical model

Model-conditioned parameter inference

Update parameter distributions from calibrated observations under explicit physical likelihoods and priors.

Inputs

  • calibrated data
  • physical likelihood
  • parameter priors

Outputs

  • posterior estimates
  • model checks
  • prior sensitivity

Transformation: Compute posterior distributions and predictive diagnostics.

Limit: Posterior precision is conditional on the selected model family.

Open connected system →
Empirical validationempirical test

Bayesian rule-pruning protocol

Update bounded rule-effect estimates while shrinking noisy factors and preserving null results.

Inputs

  • pre-registered rule features
  • objective outcomes
  • hierarchical prior

Outputs

  • posterior effect distributions
  • shrinkage diagnostics
  • retained and pruned candidates

Transformation: Fit a versioned hierarchical model and run prior and posterior predictive checks.

Limit: Pruning on one dataset can overfit; retained rules require prospective replication.

Open connected system →

Authoritative references

  1. [1]NIST/SEMATECH e-Handbook of Statistical Methods · National Institute of Standards and Technology

    Establishes: Methods for uncertainty analysis, calibration, time-series modeling, process monitoring, experimental design, reliability, and statistical comparison.

    Boundary: Statistical procedures quantify evidence under a design and model; they do not repair biased sampling, outcome leakage, post-hoc hypotheses, or unmeasured confounding.

Related mathematical concepts