An Objective Justification of Bayesianism I: Measuring Inaccuracy

Leitgeb, Hannes and Pettigrew, Richard (2010): An Objective Justification of Bayesianism I: Measuring Inaccuracy. In: Philosophy of Science, Vol. 77, No. 2: pp. 201-235

Abstract

In this article and its sequel, we derive Bayesianism from the following norm: Accuracy: An agent ought to minimize the inaccuracy of her partial beliefs. In this article, we make this norm mathematically precise. We describe epistemic dilemmas an agent might face if she attempts to follow Accuracy and show that the only measures of inaccuracy that do not create these dilemmas are the quadratic inaccuracy measures. In the sequel, we derive Bayesianism from Accuracy and show that Jeffrey Conditionalization violates Accuracy unless Rigidity is assumed. We describe the alternative updating rule that Accuracy mandates in the absence of Rigidity.

• Item Type: Journal article
• Faculties: Philosophy, Philosophy of Science and Religious Science > Munich Center for Mathematical Philosophy (MCMP); Philosophy, Philosophy of Science and Religious Science > Munich Center for Mathematical Philosophy (MCMP) > Logic
• Subjects: 100 Philosophy and Psychology > 160 Logic
• ISSN: 0031-8248
• Language: English