Pretty cool to see the viz. I've never found a great improvement with LSI / PCA on text if trying to classify information. A lot of the work in IR seems to sug

Pretty cool to see the viz. I've never found a great improvement with LSI / PCA on text if trying to classify information. A lot of the work in IR seems to suggest improvements in NLP don't improve various ranking models (TF,BM,LM). I wonder do people just revert to lsi / plsi / pca because its fast to compute?