Thanks for pointing out these two plots that can help identify where we see these divergences. Comparing Figure 1 to 2, we can say log(tau) might have a convergence issue when it is small, approaching 0 (divergences–green dots–appear in the place around 0). What else can we read from Figure 2?
Since the green dots in Figure 2 do not show us a clear pattern of concentration or anything else, can we simply remove them from the trace data stored in the az.InferenceData and use the az.InferenceData without divergences to do further posterior inference?
The fact that the non-centered specification yields decent sampling with a target acceptance of 0.8 suggests that it is relatively high (high ESS/draw).
ESS is a number indicating the efficiency of an algorithm. In general, is high ESS/draw a bad signal?
Figure 1
Figure 2
