Mixture of hierarchical model

Also, you might find some inspiration from this question:

I had two notebook that explore different parameterization and inference:
https://github.com/junpenglao/Planet_Sakaar_Data_Science/blob/master/PyMC3QnA/mixture/Mixture_discourse.ipynb
https://github.com/junpenglao/Planet_Sakaar_Data_Science/blob/master/PyMC3QnA/mixture/Mixture_discourse_order.ipynb