| rare-package | Model path for tree-based lasso framework for selecting rare features |
| data.dtm | Document-term matrix for adjectives in TripAdvisor hotel reviews |
| data.hc | Hierarchical clustering tree for adjectives in TripAdvisor data set |
| data.rating | TripAdvisor hotel review ratings |
| find.leaves | Find all descendant leaves of a node in an hclust tree |
| group.plot | Visualize groups by coloring branches and leaves of an hclust tree |
| group.recover | Recover aggregated groups of leaf indices |
| rarefit | Fit the rare feature selection model |
| rarefit.cv | Perform K-fold cross validation |
| rarefit.predict | Make predictions from a rarefit object and a rarefit.cv object |
| tree.matrix | Generate matrix A encoding ancestor-descendant relationships in an hclust tree |