| arbor | Recursive Partitioning and Regression Trees | 
| arbor.anova | Set Up for anova Method for an Arbor Model | 
| arbor.class | Set Up for Class Method for an Arbor Model | 
| arbor.control | Control for Arbor Models | 
| arbor.matrix | Create a Model Matrix for Arbor | 
| arbor.object | Recursive Partitioning and Regression Trees Object | 
| labels.arbor | Create Split Labels for an Arbor Object | 
| model.frame.arbor | Create a Model Frame for Fitting an Arbor Object | 
| na.arbor | Handles Missing Values in an Arbor Object | 
| predict.arbor | Predictions from a Arbor Object | 
| print.arbor | Print an Arbor Object | 
| printcp | Displays CP table for Fitted Arbor Object | 
| prune.arbor | Cost-complexity Pruning of an Arbor Object | 
| residuals.arbor | Residuals from an Arbor Object | 
| summary.arbor | Summarize an Arbor Object | 
| xpred.arbor | Return Cross-Validated Predictions |