Introducing Markov Chain Monte Carlo: A Powerful Tool for Simulations and Beyond

Moklesur Rahman
4 min readJul 24, 2023
Photo by Holly Mindrup on Unsplash

In the world of statistical simulations and data analysis, Markov Chain Monte Carlo (MCMC) has emerged as a powerful and versatile technique. Initially developed in the 1940s, MCMC gained significant traction in the last few decades as computational power increased. Its applications span across various fields, including physics, computer science, engineering, finance, and even artificial intelligence. In this blog post, we will dive into the concept of Markov Chain Monte Carlo, explore its principles, and highlight some of its exciting applications.

Understanding the Basics of Markov Chain Monte Carlo: At its core, Markov Chain Monte Carlo is a probabilistic method used to sample from complex probability distributions. These distributions often arise in scenarios where traditional sampling methods like direct sampling or rejection sampling are infeasible due to high dimensionality or intractable likelihood functions. MCMC tackles this challenge by constructing a Markov Chain, where each state of the chain represents a sample from the target distribution. By employing carefully designed transition rules, the Markov Chain explores the distribution over time, converging to a stationary distribution that matches the desired target.

Let's explain Markov Chain Monte Carlo (MCMC) with an analogy involving a wandering explorer looking for hidden treasure on a mysterious island.

Imagine that you are an explorer, and you've arrived on a large, uncharted island to find the legendary "X" that marks the location of hidden treasure. However, the island is dense with fog, and you can't see far ahead. To make matters more complicated, the terrain is rugged, with hills, valleys, and thick vegetation. You also can't retrace your steps, and your visibility is limited to a small area around you.

Your goal is to find the treasure (the optimal solution) by wandering around the island in the fog, but you can only move in small steps due to the challenging terrain. So, you decide to use a technique called Markov Chain Monte Carlo to guide your exploration.

Here's how the analogy relates to MCMC:

  1. Current State: At any given moment, your location on the island represents your current…

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Moklesur Rahman

PhD student | Computer Science | University of Milan | Data science | AI in Cardiology | Writer | Researcher