Posterior retrodictive checks

Hi all, I’m currently learning how to use Numpyro and run some MCMC chains. as I’m really new in this field I’m reading a lot of article to try to decipher this approach. I’ve been advise to read the “Bayesian principle workflow” of Betancourt, it’s actually really useful even if not trivial to understand sometime.
More especially in the web article he refers to “posterior retrodictive checks”, I’ve heard of “posterior prédictive check” and “prior prédictive check” but “retroactive” is brand new.

This leads me to wonder if it is useful ? How can I perform one in Numpyro ?