From the post:
This post is a follow-up to last year’s How to Create Topic Clouds with Lexos, where I showed how Lexos can be used to visualise topic models produced by Mallet. From time to time, colleagues have wondered whether it would be possible to use Lexos to perform cluster analysis on the topics Mallet produces. The motivation for doing this is simple enough; topics are often very similar, and it would be useful to have some statistical measure of this similarity to help us decide where groups of topics really should be interpreted under some meta-class.