weka.associations

## Class Apriori

- java.lang.Object
- - weka.associations.AbstractAssociator
  - - weka.associations.Apriori

- All Implemented Interfaces:
    java.io.Serializable, java.lang.Cloneable, AssociationRulesProducer, Associator, CARuleMiner, CapabilitiesHandler, CapabilitiesIgnorer, OptionHandler, RevisionHandler, TechnicalInformationHandler

      public class Apriori
      extends AbstractAssociator
      implements OptionHandler, AssociationRulesProducer, CARuleMiner, TechnicalInformationHandler

  Class implementing an Apriori-type algorithm. Iteratively reduces the minimum support until it finds the required number of rules with the given minimum confidence.
  The algorithm has an option to mine class association rules. It is adapted as explained in the second reference.
  For more information see:
  R. Agrawal, R. Srikant: Fast Algorithms for Mining Association Rules in Large Databases. In: 20th International Conference on Very Large Data Bases, 478-499, 1994.
  Bing Liu, Wynne Hsu, Yiming Ma: Integrating Classification and Association Rule Mining. In: Fourth International Conference on Knowledge Discovery and Data Mining, 80-86, 1998.

  BibTeX:

       @inproceedings{Agrawal1994,
          author = {R. Agrawal and R. Srikant},
          booktitle = {20th International Conference on Very Large Data Bases},
          pages = {478-499},
          publisher = {Morgan Kaufmann, Los Altos, CA},
          title = {Fast Algorithms for Mining Association Rules in Large Databases},
          year = {1994}
       }

       @inproceedings{Liu1998,
          author = {Bing Liu and Wynne Hsu and Yiming Ma},
          booktitle = {Fourth International Conference on Knowledge Discovery and Data Mining},
          pages = {80-86},
          publisher = {AAAI Press},
          title = {Integrating Classification and Association Rule Mining},
          year = {1998}
       }

  Valid options are:

       -N <required number of rules output>
        The required number of rules. (default = 10)

       -T <0=confidence | 1=lift | 2=leverage | 3=Conviction>
        The metric type by which to rank rules. (default = confidence)

       -C <minimum metric score of a rule>
        The minimum confidence of a rule. (default = 0.9)

       -D <delta for minimum support>
        The delta by which the minimum support is decreased in
        each iteration. (default = 0.05)

       -U <upper bound for minimum support>
        Upper bound for minimum support. (default = 1.0)

       -M <lower bound for minimum support>
        The lower bound for the minimum support. (default = 0.1)

       -S <significance level>
        If used, rules are tested for significance at
        the given level. Slower. (default = no significance testing)

       -I
        If set the itemsets found are also output. (default = no)

       -R
        Remove columns that contain all missing values (default = no)

       -V
        Report progress iteratively. (default = no)

       -A
        If set class association rules are mined. (default = no)

       -Z
        Treat zero (i.e. first value of nominal attributes) as missing

       -B <toString delimiters>
        If used, two characters to use as rule delimiters
        in the result of toString: the first to delimit fields,
        the second to delimit items within fields.
        (default = traditional toString result)

       -c <the class index>
        The class index. (default = last)

  Version:
    $Revision: 10203 $
  Author:
    Eibe Frank (eibe@cs.waikato.ac.nz), Mark Hall (mhall@cs.waikato.ac.nz), Stefan Mutter (mutter@cs.waikato.ac.nz)
  See Also:
    Serialized Form

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `static Tag[]` | `TAGS_SELECTION` Metric types.

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `Apriori()` Constructor that allows to sets default values for the minimum confidence and the maximum number of rules the minimum confidence.

  - ### Method Summary

    Methods
    Modifier and Type | Method and Description
    --- | ---
    `void` | `buildAssociations(Instances instances)` Method that generates all large itemsets with a minimum support, and from these all association rules with a minimum confidence.
    `boolean` | `canProduceRules()` Returns true if this AssociationRulesProducer can actually produce rules.
    `java.lang.String` | `carTipText()` Returns the tip text for this property
    `java.lang.String` | `classIndexTipText()` Returns the tip text for this property
    `java.lang.String` | `deltaTipText()` Returns the tip text for this property
    `java.util.ArrayList<java.lang.Object>[]` | `getAllTheRules()` returns all the rules
    `AssociationRules` | `getAssociationRules()` Gets the list of mined association rules.
    `Capabilities` | `getCapabilities()` Returns default capabilities of the classifier.
    `boolean` | `getCar()` Gets whether class association ruels are mined
    `int` | `getClassIndex()` Gets the class index
    `double` | `getDelta()` Get the value of delta.
    `Instances` | `getInstancesNoClass()` Gets the instances without the class atrribute.
    `Instances` | `getInstancesOnlyClass()` Gets only the class attribute of the instances.
    `double` | `getLowerBoundMinSupport()` Get the value of lowerBoundMinSupport.
    `SelectedTag` | `getMetricType()` Get the metric type
    `double` | `getMinMetric()` Get the value of minConfidence.
    `int` | `getNumRules()` Get the value of numRules.
    `java.lang.String[]` | `getOptions()` Gets the current settings of the Apriori object.
    `boolean` | `getOutputItemSets()` Gets whether itemsets are output as well
    `boolean` | `getRemoveAllMissingCols()` Returns whether columns containing all missing values are to be removed
    `java.lang.String` | `getRevision()` Returns the revision string.
    `java.lang.String[]` | `getRuleMetricNames()` Gets a list of the names of the metrics output for each rule.
    `double` | `getSignificanceLevel()` Get the value of significanceLevel.
    `TechnicalInformation` | `getTechnicalInformation()` Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.
    `boolean` | `getTreatZeroAsMissing()` Gets whether zeros (i.e.
    `double` | `getUpperBoundMinSupport()` Get the value of upperBoundMinSupport.
    `boolean` | `getVerbose()` Gets whether algorithm is run in verbose mode
    `java.lang.String` | `globalInfo()` Returns a string describing this associator
    `java.util.Enumeration<Option>` | `listOptions()` Returns an enumeration describing the available options.
    `java.lang.String` | `lowerBoundMinSupportTipText()` Returns the tip text for this property
    `static void` | `main(java.lang.String[] args)` Main method.
    `java.lang.String` | `metricString()` Returns the metric string for the chosen metric type
    `java.lang.String` | `metricTypeTipText()` Returns the tip text for this property
    `java.util.ArrayList<java.lang.Object>[]` | `mineCARs(Instances data)` Method that mines all class association rules with minimum support and with a minimum confidence.
    `java.lang.String` | `minMetricTipText()` Returns the tip text for this property
    `java.lang.String` | `numRulesTipText()` Returns the tip text for this property
    `java.lang.String` | `outputItemSetsTipText()` Returns the tip text for this property
    `java.lang.String` | `removeAllMissingColsTipText()` Returns the tip text for this property
    `void` | `resetOptions()` Resets the options to the default values.
    `void` | `setCar(boolean flag)` Sets class association rule mining
    `void` | `setClassIndex(int index)` Sets the class index
    `void` | `setDelta(double v)` Set the value of delta.
    `void` | `setLowerBoundMinSupport(double v)` Set the value of lowerBoundMinSupport.
    `void` | `setMetricType(SelectedTag d)` Set the metric type for ranking rules
    `void` | `setMinMetric(double v)` Set the value of minConfidence.
    `void` | `setNumRules(int v)` Set the value of numRules.
    `void` | `setOptions(java.lang.String[] options)` Parses a given list of options.
    `void` | `setOutputItemSets(boolean flag)` Sets whether itemsets are output as well
    `void` | `setRemoveAllMissingCols(boolean r)` Remove columns containing all missing values.
    `void` | `setSignificanceLevel(double v)` Set the value of significanceLevel.
    `void` | `setTreatZeroAsMissing(boolean z)` Sets whether zeros (i.e.
    `void` | `setUpperBoundMinSupport(double v)` Set the value of upperBoundMinSupport.
    `void` | `setVerbose(boolean flag)` Sets verbose mode
    `java.lang.String` | `significanceLevelTipText()` Returns the tip text for this property
    `java.lang.String` | `toString()` Outputs the size of all the generated sets of itemsets and the rules.
    `java.lang.String` | `treatZeroAsMissingTipText()` Returns the tip text for this property
    `java.lang.String` | `upperBoundMinSupportTipText()` Returns the tip text for this property
    `java.lang.String` | `verboseTipText()` Returns the tip text for this property

    - ### Methods inherited from class weka.associations.AbstractAssociator

      `doNotCheckCapabilitiesTipText, forName, getDoNotCheckCapabilities, makeCopies, makeCopy, runAssociator, setDoNotCheckCapabilities`

    - ### Methods inherited from class java.lang.Object

      `equals, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- - ### Field Detail

    - #### TAGS_SELECTION

          public static final Tag[] TAGS_SELECTION

      Metric types.

  - ### Constructor Detail

    - #### Apriori

          public Apriori()

      Constructor that allows to sets default values for the minimum confidence and the maximum number of rules the minimum confidence.

  - ### Method Detail

    - #### globalInfo

          public java.lang.String globalInfo()

      Returns a string describing this associator
      Returns:
        a description of the evaluator suitable for displaying in the explorer/experimenter gui

    - #### getTechnicalInformation

          public TechnicalInformation getTechnicalInformation()

      Returns an instance of a TechnicalInformation object, containing detailed information about the technical background of this class, e.g., paper reference or book this class is based on.
      Specified by:
        `getTechnicalInformation` in interface `TechnicalInformationHandler`
      Returns:
        the technical information about this class

    - #### resetOptions

          public void resetOptions()

      Resets the options to the default values.

    - #### getCapabilities

          public Capabilities getCapabilities()

      Returns default capabilities of the classifier.
      Specified by:
        `getCapabilities` in interface `Associator`
      Specified by:
        `getCapabilities` in interface `CapabilitiesHandler`
      Overrides:
        `getCapabilities` in class `AbstractAssociator`
      Returns:
        the capabilities of this classifier
      See Also:
        `Capabilities`

    - #### buildAssociations

          public void buildAssociations(Instances instances)
                                 throws java.lang.Exception

      Method that generates all large itemsets with a minimum support, and from these all association rules with a minimum confidence.
      Specified by:
        `buildAssociations` in interface `Associator`
      Parameters:
        `instances` - the instances to be used for generating the associations
      Throws:
        `java.lang.Exception` - if rules can't be built successfully

    - #### mineCARs

          public java.util.ArrayList<java.lang.Object>[] mineCARs(Instances data)
                                                           throws java.lang.Exception

      Method that mines all class association rules with minimum support and with a minimum confidence.
      Specified by:
        `mineCARs` in interface `CARuleMiner`
      Parameters:
        `data` - the instances for which class association rules should be mined
      Returns:
        an sorted array of FastVector (confidence depended) containing the rules and metric information
      Throws:
        `java.lang.Exception` - if rules can't be built successfully

    - #### getInstancesNoClass

          public Instances getInstancesNoClass()

      Gets the instances without the class atrribute.
      Specified by:
        `getInstancesNoClass` in interface `CARuleMiner`
      Returns:
        the instances without the class attribute.

    - #### getInstancesOnlyClass

          public Instances getInstancesOnlyClass()

      Gets only the class attribute of the instances.
      Specified by:
        `getInstancesOnlyClass` in interface `CARuleMiner`
      Returns:
        the class attribute of all instances.

    - #### listOptions

          public java.util.Enumeration<Option> listOptions()

      Returns an enumeration describing the available options.
      Specified by:
        `listOptions` in interface `OptionHandler`
      Returns:
        an enumeration of all the available options.

    - #### setOptions

          public void setOptions(java.lang.String[] options)
                          throws java.lang.Exception

      Parses a given list of options.

      Valid options are:

           -N <required number of rules output>
            The required number of rules. (default = 10)

           -T <0=confidence | 1=lift | 2=leverage | 3=Conviction>
            The metric type by which to rank rules. (default = confidence)

           -C <minimum metric score of a rule>
            The minimum confidence of a rule. (default = 0.9)

           -D <delta for minimum support>
            The delta by which the minimum support is decreased in
            each iteration. (default = 0.05)

           -U <upper bound for minimum support>
            Upper bound for minimum support. (default = 1.0)

           -M <lower bound for minimum support>
            The lower bound for the minimum support. (default = 0.1)

           -S <significance level>
            If used, rules are tested for significance at
            the given level. Slower. (default = no significance testing)

           -I
            If set the itemsets found are also output. (default = no)

           -R
            Remove columns that contain all missing values (default = no)

           -V
            Report progress iteratively. (default = no)

           -A
            If set class association rules are mined. (default = no)

           -Z
            Treat zero (i.e. first value of nominal attributes) as missing

           -B <toString delimiters>
            If used, two characters to use as rule delimiters
            in the result of toString: the first to delimit fields,
            the second to delimit items within fields.
            (default = traditional toString result)

           -c <the class index>
            The class index. (default = last)

      Specified by:
        `setOptions` in interface `OptionHandler`
      Parameters:
        `options` - the list of options as an array of strings
      Throws:
        `java.lang.Exception` - if an option is not supported

    - #### getOptions

          public java.lang.String[] getOptions()

      Gets the current settings of the Apriori object.
      Specified by:
        `getOptions` in interface `OptionHandler`
      Returns:
        an array of strings suitable for passing to setOptions

    - #### toString

          public java.lang.String toString()

      Outputs the size of all the generated sets of itemsets and the rules.
      Overrides:
        `toString` in class `java.lang.Object`
      Returns:
        a string representation of the model

    - #### metricString

          public java.lang.String metricString()

      Returns the metric string for the chosen metric type
      Specified by:
        `metricString` in interface `CARuleMiner`
      Returns:
        a string describing the used metric for the interestingness of a class association rule

    - #### removeAllMissingColsTipText

          public java.lang.String removeAllMissingColsTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### setRemoveAllMissingCols

          public void setRemoveAllMissingCols(boolean r)

      Remove columns containing all missing values.
      Parameters:
        `r` - true if cols are to be removed.

    - #### getRemoveAllMissingCols

          public boolean getRemoveAllMissingCols()

      Returns whether columns containing all missing values are to be removed
      Returns:
        true if columns are to be removed.

    - #### upperBoundMinSupportTipText

          public java.lang.String upperBoundMinSupportTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### getUpperBoundMinSupport

          public double getUpperBoundMinSupport()

      Get the value of upperBoundMinSupport.
      Returns:
        Value of upperBoundMinSupport.

    - #### setUpperBoundMinSupport

          public void setUpperBoundMinSupport(double v)

      Set the value of upperBoundMinSupport.
      Parameters:
        `v` - Value to assign to upperBoundMinSupport.

    - #### setClassIndex

          public void setClassIndex(int index)

      Sets the class index
      Specified by:
        `setClassIndex` in interface `CARuleMiner`
      Parameters:
        `index` - the class index

    - #### getClassIndex

          public int getClassIndex()

      Gets the class index
      Returns:
        the index of the class attribute

    - #### classIndexTipText

          public java.lang.String classIndexTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### setCar

          public void setCar(boolean flag)

      Sets class association rule mining
      Parameters:
        `flag` - if class association rules are mined, false otherwise

    - #### getCar

          public boolean getCar()

      Gets whether class association ruels are mined
      Returns:
        true if class association rules are mined, false otherwise

    - #### carTipText

          public java.lang.String carTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### lowerBoundMinSupportTipText

          public java.lang.String lowerBoundMinSupportTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### getLowerBoundMinSupport

          public double getLowerBoundMinSupport()

      Get the value of lowerBoundMinSupport.
      Returns:
        Value of lowerBoundMinSupport.

    - #### setLowerBoundMinSupport

          public void setLowerBoundMinSupport(double v)

      Set the value of lowerBoundMinSupport.
      Parameters:
        `v` - Value to assign to lowerBoundMinSupport.

    - #### getMetricType

          public SelectedTag getMetricType()

      Get the metric type
      Returns:
        the type of metric to use for ranking rules

    - #### metricTypeTipText

          public java.lang.String metricTypeTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### setMetricType

          public void setMetricType(SelectedTag d)

      Set the metric type for ranking rules
      Parameters:
        `d` - the type of metric

    - #### minMetricTipText

          public java.lang.String minMetricTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### getMinMetric

          public double getMinMetric()

      Get the value of minConfidence.
      Returns:
        Value of minConfidence.

    - #### setMinMetric

          public void setMinMetric(double v)

      Set the value of minConfidence.
      Parameters:
        `v` - Value to assign to minConfidence.

    - #### numRulesTipText

          public java.lang.String numRulesTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### getNumRules

          public int getNumRules()

      Get the value of numRules.
      Returns:
        Value of numRules.

    - #### setNumRules

          public void setNumRules(int v)

      Set the value of numRules.
      Parameters:
        `v` - Value to assign to numRules.

    - #### deltaTipText

          public java.lang.String deltaTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### getDelta

          public double getDelta()

      Get the value of delta.
      Returns:
        Value of delta.

    - #### setDelta

          public void setDelta(double v)

      Set the value of delta.
      Parameters:
        `v` - Value to assign to delta.

    - #### significanceLevelTipText

          public java.lang.String significanceLevelTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### getSignificanceLevel

          public double getSignificanceLevel()

      Get the value of significanceLevel.
      Returns:
        Value of significanceLevel.

    - #### setSignificanceLevel

          public void setSignificanceLevel(double v)

      Set the value of significanceLevel.
      Parameters:
        `v` - Value to assign to significanceLevel.

    - #### setOutputItemSets

          public void setOutputItemSets(boolean flag)

      Sets whether itemsets are output as well
      Parameters:
        `flag` - true if itemsets are to be output as well

    - #### getOutputItemSets

          public boolean getOutputItemSets()

      Gets whether itemsets are output as well
      Returns:
        true if itemsets are output as well

    - #### outputItemSetsTipText

          public java.lang.String outputItemSetsTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### setVerbose

          public void setVerbose(boolean flag)

      Sets verbose mode
      Parameters:
        `flag` - true if algorithm should be run in verbose mode

    - #### getVerbose

          public boolean getVerbose()

      Gets whether algorithm is run in verbose mode
      Returns:
        true if algorithm is run in verbose mode

    - #### verboseTipText

          public java.lang.String verboseTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### treatZeroAsMissingTipText

          public java.lang.String treatZeroAsMissingTipText()

      Returns the tip text for this property
      Returns:
        tip text for this property suitable for displaying in the explorer/experimenter gui

    - #### setTreatZeroAsMissing

          public void setTreatZeroAsMissing(boolean z)

      Sets whether zeros (i.e. the first value of a nominal attribute) should be treated as missing values.
      Parameters:
        `z` - true if zeros should be treated as missing values.

    - #### getTreatZeroAsMissing

          public boolean getTreatZeroAsMissing()

      Gets whether zeros (i.e. the first value of a nominal attribute) is to be treated int he same way as missing values.
      Returns:
        true if zeros are to be treated like missing values.

    - #### getAllTheRules

          public java.util.ArrayList<java.lang.Object>[] getAllTheRules()

      returns all the rules
      Returns:
        all the rules
      See Also:
        `m_allTheRules`

    - #### getAssociationRules

          public AssociationRules getAssociationRules()

      Description copied from interface: `AssociationRulesProducer`
      Gets the list of mined association rules.
      Specified by:
        `getAssociationRules` in interface `AssociationRulesProducer`
      Returns:
        the list of association rules discovered during mining. Returns null if mining hasn't been performed yet.

    - #### getRuleMetricNames

          public java.lang.String[] getRuleMetricNames()

      Gets a list of the names of the metrics output for each rule. This list should be the same (in terms of the names and order thereof) as that produced by AssociationRule.getMetricNamesForRule().
      Specified by:
        `getRuleMetricNames` in interface `AssociationRulesProducer`
      Returns:
        an array of the names of the metrics available for each rule learned by this producer.

    - #### canProduceRules

          public boolean canProduceRules()

      Returns true if this AssociationRulesProducer can actually produce rules. Most implementing classes will always return true from this method (obviously :-)). However, an implementing class that actually acts as a wrapper around things that may or may not implement AssociationRulesProducer will want to return false if the thing they wrap can't produce rules.
      Specified by:
        `canProduceRules` in interface `AssociationRulesProducer`
      Returns:
        true if this producer can produce rules in its current configuration

    - #### getRevision

          public java.lang.String getRevision()

      Returns the revision string.
      Specified by:
        `getRevision` in interface `RevisionHandler`
      Overrides:
        `getRevision` in class `AbstractAssociator`
      Returns:
        the revision

    - #### main

          public static void main(java.lang.String[] args)

      Main method.
      Parameters:
        `args` - the commandline options