Banburismus

Banburismus was a cryptanalytic process developed by Alan Turing at Bletchley Park in Britain during the Second World War.^[1] It was used by Bletchley Park's Hut 8 to help break German Kriegsmarine (naval) messages enciphered on Enigma machines. The process used sequential conditional probability to infer information about the likely settings of the Enigma machine.^[2] It gave rise to Turing's invention of the ban as a measure of the weight of evidence in favour of a hypothesis.^[3]^[4] This concept was later applied in Turingery and all the other methods used for breaking the Lorenz cipher.^[5]

^ Simpson, Edward, Chapter 13, Introducing Banburismus and Chapter 38, Banburismus revisited: depths and Bayes. In Copeland, B. Jack; Bowen, Jonathan P.; Wilson, Robin; Sprevak, Mark (2017). The Turing Guide. Oxford University Press. ISBN 978-0198747826.
^ Although this method is frequently stated to be an example of Bayesian inference, Donald Gilles has argued (Gilles, Donald (1990), "The Turing-Good Weight of Evidence Function and Popper's Measure of the Severity of a Test", Br. J. Phil. Sci., vol. 41, pp. 143–146), that the process is not really Bayesian, but rather Popperian.
^ Hodges, Andrew (1992), Alan Turing: The Enigma, London: Vintage, p. 197, ISBN 978-0-09-911641-7
^ Good, I.J. (1979). "Studies in the History of Probability and Statistics. XXXVII A. M. Turing's statistical work in World War II". Biometrika. 66 (2): 393–396. doi:10.1093/biomet/66.2.393. MR 0548210.
^ Copeland, Jack (2006), "Turingery", in Copeland, B. Jack (ed.), Colossus: The Secrets of Bletchley Park's Codebreaking Computers, Oxford: Oxford University Press, pp. 378–385, ISBN 978-0-19-284055-4