先验概率问题及其解决

The Problem of the Priors and Its

由于主观贝叶斯主义主张,只要不违反一致性规范,一个理性的认知主体对一个假说的先验概率的赋值不再受其它限制。其批评者认为科学的客观性会因此被遗失。这就是主观贝叶斯主义面临的最大问题——先验概率问题。回应此批评的方案可分为两种:(1)先验概率的确不体现科学的客观性,但是随着经验证据的累积,不同认知主体后验概率的收敛则体现了科学的客观性。(2)用主体间概率代替主观概率。科学共同体的主体间概率是客观性的体现。在分析上述回应方案面临的困难后,尝试提出共同体概率,用共同体概率代替主观概率,以期解决先验概率问题。

Subjective Bayesianism is the view that every prior probability is permitted unless it fails to be coherent.This loose condition leads to a serious problem which was called the problem of the priors.There are two kind of solutions.One accepted part view of their critic that every prior don't embody the objectivity of science,but the posterior probability do represent the objectivity.The other solution tried to replace subjective probability by intersubjective probability.Realizing those solutions'problem,this paper attempts to propose a new one which use the probability of community to replace the subjective probability.