Pietro Rigo's contribution to the Discussion of ‘Martingale Posterior Distributions’ by Fong, Holmes and Walker
Pietro Rigo 对《鞅后验分布》的讨论
This paper is really interesting and offers a number of intriguing hints. Here, I just make a few isolated remarks without any claim of being exhaustive. I would give more emphasis to the Ionescu-Tulcea theorem (ITT). This theorem is quoted only in passing, but it is the cornerstone of this paper. By ITT, the distribution of Y1:∞=(Y1,Y2,…) is completely determined by the assignment of {Pn:n≥0}, where P0(⋅)=P(Y1∈⋅) and Pn(⋅)=P(Yn+1∈⋅∣Y1:n). Exploiting ITT has at least two…