User 1251 | 2/10/2015, 3:44:19 PM
1) Allow for a holdout group when using the Vowpal Wabbit wrapper. Right now GraphLab calls VW with the --holdout_off option without any way to to do otherwise.
2) Provide a method for feature extraction from the BoostedTreesClassifier that returns leaf indices similar to the extract_features() method of NeuralNetClassifier or the apply() method of sklearn's RandomForestClassifier implementation.
3) Provide a function that does feature hashing online, rather than handle categorical variables in one large slow initial process as GraphLab currently does.