eHarmony/vowpal_wabbit — pull request #4 by pierce1987 (2013-07-09 22:59:38+00:00)
Title: 1st impl of --mask

allows the use of --mask arg to read from a regressor (binary file) and generate a binary mask from all non-zero features. The mask is applied to the training of the new model. Features with a mask 0 is blocked from training of the new model. Could be useful to first train a sparse model with -l1, the retrain the model using only survived features.