Online Bayesian Collaborative Topic Regression
This is just a Python version of Online Bayesian Collaborative Topic Regression.
The original implementation by the authors is found here.
I was inspired to look at this after reading https://open.blogs.nytimes.com/2015/08/11/building-the-next-new-york-times-recommendation-engine/ and a paper it referenced, Collaborative Topic Modeling for Recommending Scientific Articles. A straightforward implementation of CTM can be found here.
For background, some related papers are:
Variational Inference: A Review
Online Learning for Latent Dirichlet Allocation
Stochastic Variational Inference
Additional notes and citations in the code.