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

AlexAndorra October 16, 2020, 1:27pm 5

Mmmh, as if there were some mismatch in the dimension attributions in fast_sample_posterior_predictive
Pinging @rpgoldman here, as he might have some insights

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Why does sample_posterior_predictive use only one chain?

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