C45TreeBuilder

Author	Lily Dong
Creation date	06/01/2011
Firing policy	all
Package	org.seasr.meandre.components.prediction.decisiontree.c45

DESCRIPTION

Build a C4.5 decision tree. The tree is build recursively, always choosing the attribute with the highest information gain as the root. The gain ratio is used, whereby the information gain is divided by the information given by the size of the subsets that each branch creates. This prevents highly branching attributes from always becoming the root. The minimum number of records per leaf can be specified. If a leaf is created that has less than the minimum number of records per leaf, the parent will be turned into a leaf itself.

INPUTS

Name	Description	Example
exampleTable	Read org.seasr.datatypes.datamining.table.ExampleTable to build a decision tree.

OUTPUTS

Name	Description	Example
treeNode	Output the root of the decision tree built by this module. The root is of type org.seasr.meandre.support.components.prediction.decisiontree.c45.DecisionTreeNode.
error	This port is used to output any unhandled errors encountered during the execution of this component

PROPERTIES

Name	Description	Default value
verbose	Control whether debugging information is output to the console.	true
_debug_level	Controls the verbosity of debug messages printed by the component during execution. Possible values are: off, severe, warning, info, config, fine, finer, finest, all Append ',mirror' to any of the values above to mirror that output to the server logs.	info
minimumRatioPerLeaf	The minimum ratio of records in a leaf to the total number of records in the tree. The tree construction is terminated when this ratio is reached.	0.001
_ignore_errors	Set to 'true' to ignore all unhandled exceptions and prevent the flow from being terminated. Setting this property to 'false' will result in the flow being terminated in the event an unhandled exception is thrown during the execution of this component	false