# Sep 21 Rev Thomas Bayes - father of statistics

Today in 1701 Thomas Bayes was born into a prominent nonconformist family from Sheffield. He would be known for formulating: Bayes' theorem which describes the probability of an event, based on prior knowledge of conditions that might be related to the event. He wrote his findings on probability in “Essay Towards Solving a Problem in the Doctrine of Chances” (1763), but it was only published posthumously in the Philosophical Transactions of the Royal Society. That work became the basis of a statistical technique, now called Bayesian estimation. This origins of statistical thinking as well as its related philosophical questions, such as causality, determinism or chance have been dominated by two competing theories, - Bayesian and frequentist approaches – with the approach named after Thomas Bayes becoming dominant in the history of statistics and human cognition.

Thomas Bayes was the son of London Presbyterian minister Joshua Bayes, and. enrolled at the University of Edinburgh to study logic and theology. After returning from his studies he assisted his father at the latter's chapel in London before moving to Tunbridge Wells, Kent, around 1734. There he was minister of the Mount Sion Chapel, until 1752 . He was elected as a Fellow of the prestigious Royal Society in 1742 on the strength of the one mathematical work he published in his lifetime, called *An Introduction to the Doctrine of Fluxions, and a Defence of the Mathematicians Against the Objections of the Author of The Analyst* (1736), which countered the attacks by Bishop George Berkeley on the logical foundations of Sir Isaac Newton’s calculus. *The only other *work that Bayes is known to have published in his lifetime including the lengthy titled *Divine Benevolence; or, An Attempt to Prove That the Principal End of the Divine Providence and Government Is the Happiness of His Creatures* (1731)

In his later years he took a deep interest in probability after reviewing a work written in 1755 by Thomas Simpson, he was then motivated to rebut David Hume's argument against believing in miracles on the evidence of testimony in An Enquiry Concerning Human Understanding. By 1755 he was ill and by 1761 had died in Tunbridge Wells. He was buried in Bunhill Fields burial ground in Moorgate, London, where many nonconformists lie.

His fame has grown since the posthumous publication of his famous theorem, which has lead to an influential approach to statistical inference. For example, if the risk of developing health problems is known to increase with age, Bayes' theorem allows the risk to an individual of a known age to be assessed more accurately (by conditioning it on their age) than simply assuming that the individual is typical of the population as a whole. His theorem has lead to the development of Bayesian statistics. Since Bayesian statistics treats probability as a degree of belief, Bayes' theorem can directly assign a probability distribution that quantifies the belief to the parameter or set of parameters.

In several papers spanning from the late 18th to the early 19th centuries, Pierre-Simon Laplace developed the Bayesian interpretation of probability using his methods to solve a number of statistical problems. Many Bayesian methods were developed by later authors, but the term was not commonly used to describe such methods until the 1950s. During much of the 20th century, Bayesian methods were viewed unfavourably by many statisticians because they required much computation to complete, however, with the advent of powerful computers and new algorithms Bayesian methods have seen increasing use within statistics in the 21st century.

According the Steven Fienberg it wasn’t until 1970 when "Bayesian" emerged as the label of choice for those who advocated Bayesian methods. Now with Bayesian cognitive modelling is popular the University of Edinburgh opened a £45 million research centre connected to its informatics department named after its alumnus, Bayes. And then April 2021, it was announced that Cass Business School, whose City of London campus is on Bunhill Row, was to be renamed after Bayes