KNIME WEKA nodes (3.7) version 3.6.0.v201805031010 by KNIME AG, Zurich, Switzerland
Combines several classifiers using the ensemble selection method
For more information, see: Caruana, Rich, Niculescu, Alex, Crew, Geoff, and Ksikes, Alex, Ensemble Selection from Libraries of Models, The International Conference on Machine Learning (ICML'04), 2004.Implemented in Weka by Bob Jung and David Michael.
(based on WEKA 3.7)
For further options, click the 'More' - button in the dialog.
All weka dialogs have a panel where you can specify classifier-specific parameters.
L: Specifies the Model Library File, continuing the list of all models.
W: Specifies the Working Directory, where all models will be stored.
B: Set the number of bags, i.e., number of iterations to run the ensemble selection algorithm.
E: Set the ratio of library models that will be randomly chosen to populate each bag of models.
V: Set the ratio of the training data set that will be reserved for validation.
H: Set the number of hillclimbing iterations to be performed on each model bag.
I: Set the the ratio of the ensemble library that the sort initialization algorithm will be able to choose from while initializing the ensemble for each model bag
X: Sets the number of cross-validation folds.
P: Specify the metric that will be used for model selection during the hillclimbing algorithm. Valid metrics are: accuracy, rmse, roc, precision, recall, fscore, all
A: Specifies the algorithm to be used for ensemble selection. Valid algorithms are: "forward" (default) for forward selection. "backward" for backward elimination. "both" for both forward and backward elimination. "best" to simply print out top performer from the ensemble library "library" to only train the models in the ensemble library
R: Flag whether or not models can be selected more than once for an ensemble.
G: Whether sort initialization greedily stops adding models when performance degrades.
O: Flag for verbose output. Prints out performance of all selected models.
S: Random number seed. (default 1)
D: If set, classifier is run in debug mode and may output additional info to the console
The Preliminary Attribute Check tests the underlying classifier against the DataTable specification at the inport of the node. Columns that are compatible with the classifier are marked with a green 'ok'. Columns which are potentially not compatible are assigned a red error message.
Important: If a column is marked as 'incompatible', it does not necessarily mean that the classifier cannot be executed! Sometimes, the error message 'Cannot handle String class' simply means that no nominal values are available (yet). This may change during execution of the predecessor nodes.
Capabilities: [Nominal attributes, Binary attributes, Unary attributes, Empty nominal attributes, Numeric attributes, Date attributes, Missing values, Nominal class, Binary class, Numeric class] Dependencies:  min # Instance: 1
It shows the command line options according to the current classifier configuration and mainly serves to support the node's configuration via flow variables.
To use this node in KNIME, install KNIME WEKA nodes (3.7) from the following update site: