Identical twins and Bayes ' theorem in the 21 st century [

In a recent article in on "Bayes' Theorem in the 21st Century", Bradley Science Efron uses Bayes' theorem to calculate the probability that twins are identical given that the sonogram shows twin boys. He concludes that Bayesian calculations cannot be uncritically accepted when using uninformative priors. We argue that this conclusion is problematic because Efron's example on identical twins does not use data, hence it is not Bayesian statistics; his priors are not appropriate and are not uninformative; and using the available data point and an uninformative prior actually leads to a reasonable posterior distribution. Valentin Amrhein ( ) Corresponding author: [email protected] Amrhein V, Roth T and Korner-Nievergelt F. How to cite this article: Identical twins and Bayes' theorem in the 21st century [version 1; 2013, :278 (doi: ) referees: 1 not approved] F1000Research 2 10.12688/f1000research.2-278.v1 © 2013 Amrhein V . This is an open access article distributed under the terms of the , which Copyright: et al Creative Commons Attribution Licence permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Data associated with the article are available under the terms of the (CC0 1.0 Public domain dedication). Creative Commons Zero "No rights reserved" data waiver This work was funded by the Swiss Association Pro Petite Camargue Alsacienne and the Fondation de Bienfaisance Jeanne Grant information: Lovioz. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Competing interests: No competing interests were disclosed. 17 Dec 2013, :278 (doi: ) First published: 2 10.12688/f1000research.2-278.v1 1,2 1,2