I think they're talking about this one: http://projecteuclid.org/euclid.aoas/1183143727 http://projecteuclid.org/euclid.aoas/1183143727 This work uses the cor

I think they're talking about this one: http://projecteuclid.org/euclid.aoas/1183143727 http://projecteuclid.org/euclid.aoas/1183143727 This work uses the correlated topic model, which extends LDA to model correlations among the extracted topics. Edit: and this one [pdf]: http://www.icml2010.org/papers/384.pdf http://www.icml2010.org/papers/384.pdf