Template-Type: ReDIF-Paper 1.0 Author-Name: Jon Frost Author-X-Name-First: Jon Author-X-Name-Last: Frost Author-Name: Carlos Madeira Author-X-Name-First: Carlos Author-X-Name-Last: Madeira Author-Name: Yash Rastogi Author-X-Name-First: Yash Author-X-Name-Last: Rastogi Author-Name: Harald Uhlig Author-X-Name-First: Harald Author-X-Name-Last: Uhlig Title: Quantum Bayesian inference: an exploration Abstract: This paper introduces a framework for performing Bayesian inference using quantum computation. It presents a proof-of-concept quantum algorithm that performs posterior sampling. We provide an accessible introduction to quantum computation for economists and a practical demonstration of quantum-based posterior sampling for Bayesian estimation. Our key contribution is the preparation of a quantum state whose measurement yields samples from a discretised posterior distribution. While the proposed approach does not yet offer computational speedups over classical techniques such as Markov Chain Monte Carlo, it demonstrates the feasibility of simulating Bayesian inference with quantum computation. This work serves as a first step in integrating quantum computation into the econometrician's toolbox. It highlights both the conceptual promise and practical challenges – especially those related to quantum state preparation – in leveraging quantum computation for Bayesian inference. Creation-Date: 2026-04 File-URL: https://www.bis.org/publ/work1342.pdf File-Format: Application/pdf File-Function: Full PDF document File-URL: https://www.bis.org/publ/work1342.htm File-Format: text/html Number: 1342 Keywords: quantum computing; Bayesian estimator; Bayesian inference; Markov chain Monte Carlo (MCMC) algorithms; Gibbs sampling Classification-JEL: C11, C20, C30, C50, C60 Handle: RePEc:bis:biswps:1342