Learns a random forest*, which consists of a chosen number of decision trees. Each of the decision tree models is learned on a different set of rows (records) and a different set of columns (describing attributes), whereby the latter can also be a bit-vector or byte-vector descriptor (e.g. molecular fingerprint). The row sets for each decision tree are created by bootstrapping and have the same size as the original input table. For each node of a decision tree a new set of attributes is determined by taking a random sample of size sqrt(m) where m is the total number of attributes. The output model describes a random forest and is applied in the corresponding predictor node using a simply majority vote.
This node provides a subset of the functionality of the Tree Ensemble Learner corresponding to a random forest. If you need additional functionality please check out the Tree Ensemble Learner.
Experiments have shown the results on different data sets are very similar to the random Forest implementation available in R. Known differences are in the missing value handling (currently not available in this node) and the split creation for nominal attributes (the original random forest classifier uses binary nominal splits; this implementation creates child nodes for each possible split attribute).
The decision tree construction takes place in main memory (all data and all models are kept in memory).
(*) RANDOM FORESTS is a registered trademark of Minitab, LLC and is used with Minitab’s permission.
Options
Attribute Selection
Tree Options
Forest Options
Input Ports
- The data to learn from. It must contain at least one nominal target column and either a fingerprint (bit-vector/byte-vector) column or another numeric or nominal column.
Output Ports
- The input data with the out-of-bag error estimates, i.e. for each input row the majority vote of all models that did not use the row in the training. If the entire data was used to train the individual models then this output will contain the input data with missing prediction and confidence values. The appended columns are equivalent to the columns appended by the corresponding predictor node. There is one additional column model count, which contains the number of models used for the voting (number of models not using the row throughout the learning.)
- A statistics table on the attributes used in the different tree learners. Each row represents one training attribute with these statistics: #splits (level x) as the number of models, which use the attribute as split on level x (with level 0 as root split); #candidates (level x) is the number of times an attribute was in the attribute sample for level x (in a random forest setup these samples differ from node to node). If no attribute sampling is used #candidates is the number of models. Note, these numbers are uncorrected, i.e. if an attribute is selected on level 0 but is also in the candidate set of level 1 (but will not be split on level 1 because it has been split one level up), the #candidate number will still count the attribute as candidate.
- The trained model.
Popular Predecessors
- Column Filter13 %
CSV Reader8 %File Reader5 %- Missing Value5 %
Scorer4 %Double To Int4 %- Missing Value Column Filter4 %
- Partitioning3 %
Row Filter (deprecated)2 %- Rule-based Row Filter2 %
- ARFF Reader2 %
- Concatenate2 %
- Auto-Binner2 %
- Equal Size Sampling2 %
- Normalizer2 %
- Row Sampling2 %
- Decision Tree to Ruleset2 %
- Correlation Filter2 %
Column Rename2 %Document vector2 %- Number to Category (Apply)2 %
Database Reader1 %Naive Bayes Predictor1 %- Domain Calculator1 %
- Read Images< 1 %
Backward Feature Elimination Start (1:1)< 1 %- k-Means< 1 %
Random Forest Learner< 1 %- GroupBy< 1 %
Tree Ensemble Predictor< 1 %- Random Label Assigner< 1 %
K Nearest Neighbor< 1 %PCA Apply< 1 %- Column Resorter< 1 %
Joiner< 1 %- Low Variance Filter< 1 %
Merge Variables< 1 %- Crosstab< 1 %
- Parallel Chunk End< 1 %
- Chunk Loop Start< 1 %
Random Forest Predictor< 1 %Concatenate (Optional in)< 1 %- Numeric Binner (PMML)< 1 %
- Lift Chart (legacy)< 1 %
Table Row to Variable< 1 %Table Reader< 1 %- Java Edit Variable< 1 %
- X-Partitioner< 1 %
- PNN Learner (DDA)< 1 %
- Hierarchical Clustering< 1 %
- SMOTE< 1 %
- Create Bit Vector< 1 %
- Bootstrap Sampling< 1 %
- Category to Number< 1 %
Number To String< 1 %String To Number< 1 %Number To String (PMML)< 1 %- Shuffle< 1 %
- Rule Engine< 1 %
- Data Generator< 1 %
- Color Manager< 1 %
- ROC Curve (legacy)< 1 %
- Parallel Chunk Start< 1 %
- Math Formula< 1 %
- Java Snippet (simple)< 1 %
- Parameter Optimization Loop Start< 1 %
Backward Feature Elimination Start (2:2)< 1 %Counting Loop Start< 1 %Interval Loop Start< 1 %- Column List Loop Start< 1 %
- X-Aggregator< 1 %
Tree Ensemble Learner< 1 %Random Forest Learner (Regression)< 1 %- Numeric Binner< 1 %
- Expand Bit Vector< 1 %
Column Appender< 1 %- Edit Nominal Domain< 1 %
- Edit Numeric Domain< 1 %
- Reference Column Filter< 1 %
- Reference Row Splitter< 1 %
- Table Transposer< 1 %
- Statistics< 1 %
CASE Switch Data (Start)< 1 %- Extract Table Dimension< 1 %
- SDF Reader< 1 %
XLS Reader< 1 %- Column Selection (legacy)< 1 %
- Parameter Optimization Loop End< 1 %
Python Script (1⇒1)< 1 %- Fingerprints< 1 %
Views
- Tree Views
- An decision tree viewer for all the trained models. Use the spinner to iterate through the different models.
Workflows
Links
- No links available
Developers
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