How to set a seed for pm.sample?

Questions v5
2

You should use sample(random_seed=x). The best is to pass a numpy Generator, like:

rng = np.random.default_rng(666)
...
  pm.sample(random_seed=rng)
  pm.sample_prior_predictive(random_seed=rng)
  pm.sample_posterior_predictive(..., random_seed=rng)

Global seed is ignored. Multiple seeds per chain as with [666, 666, 666, 666], uses each number for each chain. It doesn’t make much sense to pass the same values, because you don’t want your chains to be identical. And since you want multiple values you can just pass rng and PyMC will draw 4 values for you.

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