Package weka.classifiers.trees.ft

Class FTtree

java.lang.Object
weka.classifiers.Classifier
weka.classifiers.trees.lmt.LogisticBase
weka.classifiers.trees.ft.FTtree
All Implemented Interfaces:
Serializable, Cloneable, CapabilitiesHandler, OptionHandler, RevisionHandler, WeightedInstancesHandler
Direct Known Subclasses:
FTInnerNode, FTLeavesNode, FTNode
public abstract class FTtree extends LogisticBase
Abstract class for Functional tree structure.
Version:
$Revision: 1.4 $
Author:
Jo\~{a}o Gama, Carlos Ferreira
See Also:

  • Constructor Details

    • FTtree

      public FTtree()

  • Method Details

    • buildClassifier

      public abstract void buildClassifier(Instances data) throws Exception
      Method for building a Functional Tree (only called for the root node). Grows an initial Functional Tree.
      Overrides:
      buildClassifier in class LogisticBase
      Parameters:
      data - the data to train with
      Throws:
      Exception - if something goes wrong

    • buildTree

      public abstract void buildTree(Instances data, SimpleLinearRegression[][] higherRegressions, double totalInstanceWeight, double higherNumParameters) throws Exception
      Abstract method for building the tree structure. Builds a logistic model, splits the node and recursively builds tree for child nodes.
      Parameters:
      data - the training data passed on to this node
      higherRegressions - An array of regression functions produced by LogitBoost at higher levels in the tree. They represent a logistic regression model that is refined locally at this node.
      totalInstanceWeight - the total number of training examples
      higherNumParameters - effective number of parameters in the logistic regression model built in parent nodes
      Throws:
      Exception - if something goes wrong

    • prune

      public abstract double prune() throws Exception
      Abstract Method that prunes a tree using C4.5 pruning procedure.
      Throws:
      Exception - if something goes wrong

    • getNumInnerNodes

      public int getNumInnerNodes()
      Method to count the number of inner nodes in the tree
      Returns:
      the number of inner nodes

    • getNumLeaves

      public int getNumLeaves()
      Returns the number of leaves in the tree. Leaves are only counted if their logistic model has changed compared to the one of the parent node.
      Returns:
      the number of leaves

    • getNodes

      public Vector getNodes()
      Return a list of all inner nodes in the tree
      Returns:
      the list of nodes

    • getNodes

      public void getNodes(Vector nodeList)
      Fills a list with all inner nodes in the tree
      Parameters:
      nodeList - the list to be filled

    • getConstError

      public int getConstError(double[] probsConst)
      Type Parameters:
      any - probsConst

    • hasModels

      public boolean hasModels()
      Returns true if the logistic regression model at this node has changed compared to the one at the parent node.
      Returns:
      whether it has changed

    • modelDistributionForInstance

      public double[] modelDistributionForInstance(Instance instance) throws Exception
      Returns the class probabilities for an instance according to the logistic model at the node.
      Parameters:
      instance - the instance
      Returns:
      the array of probabilities
      Throws:
      Exception

    • distributionForInstance

      public abstract double[] distributionForInstance(Instance instance) throws Exception
      Returns the class probabilities for an instance given by the Functional tree.
      Overrides:
      distributionForInstance in class LogisticBase
      Parameters:
      instance - the instance
      Returns:
      the array of probabilities
      Throws:
      Exception - if distribution can't be computed successfully

    • toString

      public String toString()
      Returns a description of the Functional tree (tree structure and logistic models)
      Overrides:
      toString in class LogisticBase
      Returns:
      describing string

    • numLeaves

      public int numLeaves()
      Returns the number of leaves (normal count).
      Returns:
      the number of leaves

    • numNodes

      public int numNodes()
      Returns the number of nodes.
      Returns:
      the number of nodes

    • getModelParameters

      public String getModelParameters()
      Returns a string describing the number of LogitBoost iterations performed at this node, the total number of LogitBoost iterations performed (including iterations at higher levels in the tree), and the number of training examples at this node.
      Returns:
      the describing string

    • assignIDs

      public int assignIDs(int lastID)
      Assigns unique IDs to all nodes in the tree

    • assignLeafModelNumbers

      public int assignLeafModelNumbers(int leafCounter)
      Assigns numbers to the logistic regression models at the leaves of the tree

    • modelsToString

      public String modelsToString()
      Returns a string describing the logistic regression function at the node.

    • graph

      public String graph() throws Exception
      Returns graph describing the tree.
      Throws:
      Exception - if something goes wrong

    • cleanup

      public void cleanup()
      Cleanup in order to save memory.
      Overrides:
      cleanup in class LogisticBase

    • getRevision

      public String getRevision()
      Returns the revision string.
      Specified by:
      getRevision in interface RevisionHandler
      Overrides:
      getRevision in class LogisticBase
      Returns:
      the revision