I sample my model with two chains and 600 draws each. Then I sample the posterior predictive, using pm.sample_posterior_predictive() (or its speedy cousin pm.fast_sample_posterior_predictive()). The posterior predictive dataset has one chain and 1200 draws. Why does sampling the posterior predicti…

Is there a return_inferencedata argument to sample_posterior_predictive? We have had some issues retrieving the original shape due to this internal reshaping when sampling the posterior predictive. Here it looks like it is ignoring the info in the provided trace (or posterior dataset) and independen…

Why does sample_posterior_predictive use only one chain?

Questions

bridgeland October 17, 2020, 2:28pm 13

I can create an example to show the problem, but not until Wednesday, as I am out of town for a few days, visiting my elderly father in Michigan.

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Why does sample_posterior_predictive use only one chain?

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