Skip to main content
6 events
when toggle format what by license comment
Dec 18, 2023 at 14:03 vote accept Anton Kerel
Aug 4, 2023 at 11:10 comment added Doctor Milt Hi @AntonKerel, the fact that your original experiment had 101 trials is already encoded in your posterior distribution for $\mu$. The number of trials in the new experiment ($N=40$) is just a fixed parameter. You know that the conditional distribution for the outcome you care about is $X|\mu \sim \mathrm{Bin}(40, \mu)$, but you want the marginal distribution. To get this, you need to integrate out $\mu$, i.e. average over all possible values of $\mu$ according to your posterior distribution.
Aug 4, 2023 at 10:18 comment added Anton Kerel (you can ignore $D$ in the formula's above)
Aug 4, 2023 at 10:00 comment added Anton Kerel For Binomial case, I am not sure how to write it down nicely $$ p(x=3|D, 40) = \int_{0}^{1} p(x=3|\mu, 40) p(\mu|D, 101) d\mu $$. This does not feel right since I have the posterior that has a parameter $N$=101 (2success + 99 failures) and the probability that I am trying to estimate is for $N$=40.
Aug 4, 2023 at 9:51 comment added Anton Kerel Thank you @Doctor Milt. Indeed, I am interested in doing Bayesian inference and I do not want to use point estimates (Maximum a posteriori estimates aka MAP). I found a similart formula (and I understand the logic behind it) to the last one you posted. It is for Bernnoulli case $$ p(x=1|D) = \int_{0}^{1} p(x=1|\mu) p(\mu|D) d\mu = \int_{0}^{1} \mu p( \mu | D) $$.
Aug 3, 2023 at 15:32 history answered Doctor Milt CC BY-SA 4.0