id3
Class ThresholdCategorizer

java.lang.Object
  |
  +--shared.Globals
        |
        +--shared.Categorizer
              |
              +--id3.NodeCategorizer
                    |
                    +--id3.ThresholdCategorizer

public class ThresholdCategorizer

extends NodeCategorizer

Categorize an instance by comparing the value of a single attribute to a threshold value. All instances for which the attribute is less than or equal to the threshold value are put into one category and those for which the attribute is greater than the threshold value are put into a second category. The attribute must be Real.

Fields inherited from class shared.Categorizer

CATEGORIZER_ID_BASE, CLASS_ATTR_CATEGORIZER, CLASS_ATTR_EQ_CATEGORIZER, CLASS_ATTR_SUBSET_CATEGORIZER, CLASS_BAD_CATEGORIZER, CLASS_BAGGING_CATEGORIZER, CLASS_CASCADE_CATEGORIZER, CLASS_CLUSTER_CATEGORIZER, CLASS_CONST_CATEGORIZER, CLASS_CONSTRUCT_CATEGORIZER, CLASS_DISC_CATEGORIZER, CLASS_DISC_NODE_CATEGORIZER, CLASS_DTREE_CATEGORIZER, CLASS_IB_CATEGORIZER, CLASS_LAZYDT_CATEGORIZER, CLASS_LEAF_CATEGORIZER, CLASS_LINDISCR_CATEGORIZER, CLASS_MAJORITY_CATEGORIZER, CLASS_MULTI_SPLIT_CATEGORIZER, CLASS_MULTITHRESH_CATEGORIZER, CLASS_NB_CATEGORIZER, CLASS_ODT_CATEGORIZER, CLASS_ONE_R_CATEGORIZER, CLASS_OPTION_CATEGORIZER, CLASS_PROJECT_CATEGORIZER, CLASS_RDG_CATEGORIZER, CLASS_STACKING_CATEGORIZER, CLASS_TABLE_CATEGORIZER, CLASS_THRESHOLD_CATEGORIZER, logOptions

Fields inherited from class shared.Globals

badCategorizer, CONFIDENCE_INTERVAL_Z, DBG, DEFAULT_DATA_EXT, DEFAULT_EPSILON, DEFAULT_EVAL_LIMIT, DEFAULT_LAMBDA, DEFAULT_MAX_EVALS, DEFAULT_MAX_STALE, DEFAULT_MIN_EXP_EVALS, DEFAULT_NAMES_EXT, DEFAULT_SAS_SEED, DEFAULT_SEARCH_METHOD, DEFAULT_SHOW_TEST_SET_PERF, DEFAULT_TEST_EXT, DISPLAY_NAMES, EMPTY_STRING, FIRST_CATEGORY_VAL, FIRST_NOMINAL_VAL, LEFT_NODE, MAX_NUM_CATEGORIES, Mcerr, Mcout, optionServer, optionsFileName, REAL_MAX, RIGHT_NODE, SHOW_TEST_SET_PERF_HELP, SINGLE_QUOTE, STORED_REAL_MAX, TS, UNDEFINED_INT, UNDEFINED_REAL, UNDEFINED_VARIANCE, UNKNOWN_AUG_CATEGORY, UNKNOWN_CATEGORY_VAL, UNKNOWN_NODE, UNKNOWN_NOMINAL_VAL, UNKNOWN_STORED_REAL_VAL, UNKNOWN_VAL_STR

Constructor Summary

ThresholdCategorizer(Schema sch, int attributeNum, double threshold, java.lang.String dscr)
Construct a ThresholdCategorizer.

Method Summary

AugCategory	branch(Instance inst) Returns the edge label leading to the node that the given instance should use to continue scoring or categorization.
void	change_threshold(double threshold) Changes the threshold value.
int	class_id() Deprecated. Use java's instanceOf function.
void	display_struct(java.io.BufferedWriter stream, DisplayPref dp) Prints a readable representation of the Categorizer to the given stream.
java.lang.String[]	real_edge_strings() Builds an array of 3 strings for the labels (?, <= x, and > x) of the edges depending from the node for which this is the categorizer.
void	set_used_attr(boolean[] usedAttr) Updates usedAttr to include the attributes used in this categorizer.

Methods inherited from class id3.NodeCategorizer

add_instance_loss, categorize, distribute_instances, get_child_categorizer, get_child_categorizer, get_graph, get_loss, get_node, in_graph, reset_node_loss, score, score, set_graph_and_node, split_instance_list, stop, supports_scoring, toString, update_loss

Methods inherited from class shared.Categorizer

build_distr, clone, description, get_distr, get_log_level, get_log_options, get_log_stream, get_schema, has_distr, num_categories, set_description, set_distr, set_log_level, set_log_options, set_log_prefixes, set_log_stream, set_original_distr, total_weight

Methods inherited from class java.lang.Object

equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

ThresholdCategorizer

public ThresholdCategorizer(Schema sch,
                            int attributeNum,
                            double threshold,
                            java.lang.String dscr)

Construct a ThresholdCategorizer.

Parameters:

sch - The schema for information this categorizer categorizes.

attributeNum - The attribute number for this threshold.

threshold - The threshold value.

dscr - Description of this categorizer.

Method Detail

change_threshold

public void change_threshold(double threshold)

Changes the threshold value.

Parameters:

threshold - The new threshold value.

class_id

public int class_id()

Deprecated. Use java's instanceOf function.

Returns the id number for this class.

Returns:

The class id number.

real_edge_strings

public java.lang.String[] real_edge_strings()

Builds an array of 3 strings for the labels (?, <= x, and > x) of the edges depending from the node for which this is the categorizer.

Returns:

An array of the strings built.

branch

public AugCategory branch(Instance inst)

Returns the edge label leading to the node that the given instance should use to continue scoring or categorization.

Overrides:

branch in class NodeCategorizer

Parameters:

inst - The instance being scored.

Returns:

Returns the category found after traversing the categorizer.

display_struct

public void display_struct(java.io.BufferedWriter stream,
                           DisplayPref dp)

Prints a readable representation of the Categorizer to the given stream.

Overrides:

display_struct in class Categorizer

Parameters:

stream - The BufferedWriter to be printed to.

dp - The display preferences.

set_used_attr

public void set_used_attr(boolean[] usedAttr)

Updates usedAttr to include the attributes used in this categorizer.

Overrides:

set_used_attr in class Categorizer

Parameters:

usedAttr - An array of used attributes. TRUE values indicate the attribute matched to that index number is used, FALSE indicates it is not.