More feedback and mallet failure with too few documents

[jeremydouglass]

from @scottkleinman:

Notebook 4

If the dfr-browser fails to generate, one common reason is that you have tried to model too few documents for MALLET to assign a positive value for the alpha hyperparameter. Alpha indicates the density of topics per document, so it cannot be a negative number, which you will see if you unzip the model/topic-state.gz generated by MALLET. A faster way to identify this problem is to look for the following error in Notebook 4:

Error in load_from_mallet_state(mallet_state_file = paste0(modelDir, "/", : hyperparameter notation missing. Is this really a file produced by mallet train-topics --output-state?