How to Evaluate a Subjective Prior Objectively

The Misconception Gelman and Hennig (2017, p. 989) argue that subjective priors cannot be evaluated by means of the data: “However, priors in the subjectivist Bayesian conception are not open to falsification (…), because by definition they must be fixed before observation. Adjusting the prior after having observed the data to be analysed violates coherence. The Bayesian system as derived…

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Did Alan Turing Invent the Bayes factor?

The otherwise excellent article by Consonni et al. (2018), discussed last week, makes the following claim: “…the initial use of the BF can be attributed both to Jeffreys and Turing who introduced it independently around the same time (Kass & Raftery, 1995)” (Consonni et al., 2018, p. 638)                   This claim recently…

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“Prior Distributions for Objective Bayesian Analysis”

The purpose of this blog post is to call attention to the paper “Prior Distributions for Objective Bayesian Analysis”, authored by Guido Consonni, Dimitris Fouskakis, Brunero Liseo, and Ioannis Ntzoufras (NB: Ioannis is a member of the JASP advisory board!). The paper –published in the journal “Bayesian Analysis”— provides a comprehensive overview of objective Bayesian analysis, with an emphasis on…

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Book Review of “Bayesian Probability for Babies”

“Bayesian Probability for Babies” is a book that explains Bayes’ rule through a simple story about cookies. I battle-tested the book on my two-year old son Theo (admittedly no longer a baby), and he seemed somewhat intrigued by the idea of candy-covered cookies, although the more subtle points of the story must have eluded him. Theo gives the book three…

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Progesterone in Women with Bleeding in Early Pregnancy: Absence of Evidence, Not Evidence of Absence

Available on https://psyarxiv.com/etk7g/, this is a comment on a recent article in the New England Journal of Medicine (Coomarasamy et al., 2019). A response by the authors will follow at a later point. A recent trial assessed the effectiveness of progesterone in preventing miscarriages.1 The number of live births was 74.7% (1513/2025) in the progesterone group and 72.5% (1459/2013) in…

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