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arviz-devs / arviz

Exploratory analysis of Bayesian models with Python
https://python.arviz.org
Apache License 2.0
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What is the meaning of bars in plot_trace graph? #2273

Closed makaishi2 closed 10 months ago

makaishi2 commented 11 months ago

I got following graph with plot_trace function. And I found many bars in it. Would you tell me what is the meaning of these bars?

Thanks,

Masanori

pdf-04-02-08

aloctavodia commented 11 months ago

Those are divergences. In a nutshell, divergences indicate that the NUTS sampler is having trouble exploring the posterior distribution. Ideally, you should have 0 divergences.

makaishi2 commented 10 months ago

I've understood it. Thank you very much!