Hi there,

I’m debugging my hierarchical multinomial logit model (which is a bit complex) that get stucked at very early iterations and I tried to simplify the model to get a minimum version that works properly.

Now I have a simplified version seems to have a normal -log_likelihood (-potential energy) curve, but when I looking at the values I found that the potential energy becomes negative after some iterations.

Here is a segment of the potential energy array where it turns from pos to neg:

…

1.4578748e+03, 1.3394178e+03, 1.2372814e+03,

9.7788623e+02, 6.7353839e+02, 4.4601050e+02,

2.3404785e+02, 9.1659241e+01, -1.0517139e+02,

-2.5695007e+02, -3.7658270e+02, -3.8519507e+02,

…

My question is – Is this expected in Numpyro?

If so, what’s the underlying mechanism about it?

If not, what’s potential problems with my code/model?

I can provide more infos about my implementation if needed.

Many Thanks!