We experimented with this hard-assignment latentdescriptor clustering algorithm (data not shown), and found that a number of additional devices were necessary in order to make it work properly.
we found it necessary to use reduced-rank SVD on each iteration of the algorithm-as opposed to just the first iteration in the version presented here-and to gradually increase the rank r. Further, we found it necessary to include only the most frequent words at the beginning, and only gradually incorporate rare words in the algorithm.