NAME¶

mlpack_random_forest - random forests

SYNOPSIS¶

 mlpack_random_forest [-m unknown] [-l string] [-D int] [-g double] [-n int] [-N int] [-a bool] [-s int] [-d int] [-T string] [-L string] [-t string] [-V bool] [-M unknown] [-p string] [-P string] [-h -v] 

DESCRIPTION¶

This program is an implementation of the standard random forest classification algorithm by Leo Breiman. A random forest can be trained and saved for later use, or a random forest may be loaded and predictions or class probabilities for points may be generated.

The training set and associated labels are specified with the '--training_file (-t)' and '--labels_file (-l)' parameters, respectively. The labels should be in the range [0, num_classes - 1]. Optionally, if '--labels_file (-l)' is not specified, the labels are assumed to be the last dimension of the training dataset.

When a model is trained, the '--output_model_file (-M)' output parameter may be used to save the trained model. A model may be loaded for predictions with the '--input_model_file (-m)'parameter. The '--input_model_file (-m)' parameter may not be specified when the '--training_file (-t)' parameter is specified. The '--minimum_leaf_size (-n)' parameter specifies the minimum number of training points that must fall into each leaf for it to be split. The '--num_trees (-N)' controls the number of trees in the random forest. The ’--minimum_gain_split (-g)' parameter controls the minimum required gain for a decision tree node to split. Larger values will force higher-confidence splits. The '--maximum_depth (-D)' parameter specifies the maximum depth of the tree. The '--subspace_dim (-d)' parameter is used to control the number of random dimensions chosen for an individual node's split. If ’--print_training_accuracy (-a)' is specified, the calculated accuracy on the training set will be printed.

Test data may be specified with the '--test_file (-T)' parameter, and if performance measures are desired for that test set, labels for the test points may be specified with the '--test_labels_file (-L)' parameter. Predictions for each test point may be saved via the '--predictions_file (-p)'output parameter. Class probabilities for each prediction may be saved with the ’--probabilities_file (-P)' output parameter.

For example, to train a random forest with a minimum leaf size of 20 using 10 trees on the dataset contained in 'data.csv'with labels 'labels.csv', saving the output random forest to 'rf_model.bin' and printing the training error, one could call

$ mlpack_random_forest --training_file data.csv --labels_file labels.csv --minimum_leaf_size 20 --num_trees 10 --output_model_file rf_model.bin --print_training_accuracy

Then, to use that model to classify points in 'test_set.csv' and print the test error given the labels 'test_labels.csv' using that model, while saving the predictions for each point to 'predictions.csv', one could call

$ mlpack_random_forest --input_model_file rf_model.bin --test_file test_set.csv --test_labels_file test_labels.csv --predictions_file predictions.csv

OPTIONAL INPUT OPTIONS¶

--help (-h) [bool]

Default help info.

--info [string]

Print help on a specific option. Default value ''.

--input_model_file (-m) [unknown]

Pre-trained random forest to use for classification.

--labels_file (-l) [string]

Labels for training dataset.

--maximum_depth (-D) [int]

Maximum depth of the tree (0 means no limit). Default value 0.

--minimum_gain_split (-g) [double]

Minimum gain needed to make a split when building a tree. Default value 0.

--minimum_leaf_size (-n) [int]

Minimum number of points in each leaf node. Default value 1.

--num_trees (-N) [int]

Number of trees in the random forest. Default value 10.

--print_training_accuracy (-a) [bool]

If set, then the accuracy of the model on the training set will be predicted (verbose must also be specified).

--seed (-s) [int]

Random seed. If 0, 'std::time(NULL)' is used. Default value 0.

--subspace_dim (-d) [int]

Dimensionality of random subspace to use for each split. '0' will autoselect the square root of data dimensionality. Default value 0.

--test_file (-T) [string]

Test dataset to produce predictions for.

--test_labels_file (-L) [string]

Test dataset labels, if accuracy calculation is desired.

--training_file (-t) [string]

Training dataset.

--verbose (-v) [bool]

Display informational messages and the full list of parameters and timers at the end of execution.

--version (-V) [bool]

Display the version of mlpack.

OPTIONAL OUTPUT OPTIONS¶

--output_model_file (-M) [unknown]

Model to save trained random forest to.

--predictions_file (-p) [string]

Predicted classes for each point in the test set.

--probabilities_file (-P) [string]

Predicted class probabilities for each point in the test set.

ADDITIONAL INFORMATION¶

For further information, including relevant papers, citations, and theory, consult the documentation found at http://www.mlpack.org or included with your distribution of mlpack.