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Class weka.classifiers.Logistic
java.lang.Object
|
+----weka.classifiers.Classifier
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+----weka.classifiers.DistributionClassifier
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+----weka.classifiers.Logistic
- public class Logistic
- extends DistributionClassifier
- implements OptionHandler
Class for building and using a two-class logistic regression model
with a ridge estimator.
This class utilizes globally convergent Newtons Method adapted from
Numerical Recipies in C.
Reference: le Cessie, S. and van Houwelingen, J.C. (1997).
Ridge Estimators in Logistic Regression. Applied Statistics,
Vol. 41, No. 1, pp. 191-201.
Missing values are replaced using a ReplaceMissingValuesFilter, and
nominal attributes are transformed into numeric attributes using a
NominalToBinaryFilter.
Valid options are:
-D
Turn on debugging output.
- Version:
- $Revision: 1.12.2.1 $
- Author:
- Len Trigg (trigg@cs.waikato.ac.nz)
- Author:
- Eibe Frank (eibe@cs.waikato.ac.nz)
- Author:
- Tony Voyle (tv6@cs.waikato.ac.nz)
Logistic()
-
buildClassifier(Instances)
- Builds the classifier
distributionForInstance(Instance)
- Computes the distribution for a given instance
getDebug()
- Gets whether debugging output will be printed.
getOptions()
- Gets the current settings of the classifier.
listOptions()
- Returns an enumeration describing the available options
lnsrch(int, double[], double, double[], double[], double[], double, double[][], double[])
- Finds a new point x in the direction p from
a point xold at which the value of the function
has decreased sufficiently.
main(String[])
- Main method for testing this class.
setDebug(boolean)
- Sets whether debugging output will be printed.
setOptions(String[])
- Parses a given list of options.
toString()
- Gets a string describing the classifier.
Logistic
public Logistic()
lnsrch
public void lnsrch(int n,
double xold[],
double fold,
double g[],
double p[],
double x[],
double stpmax,
double X[][],
double Y[]) throws java.lang.Exception
Finds a new point x in the direction p from
a point xold at which the value of the function
has decreased sufficiently.
- Parameters:
n
- number of variables
xold
- old point
fold
- value at that point
g
- gtradient at that point
p
- direction
x
- new value along direction p from xold
stpmax
- maximum step length
X
- instance data
Y
- class values
- Throws:
- java.lang.Exception - if an error occurs
listOptions
public java.util.Enumeration listOptions()
Returns an enumeration describing the available options
- 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:
-D
Turn on debugging output.
- 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 classifier.
- Returns:
- an array of strings suitable for passing to setOptions
setDebug
public void setDebug(boolean debug)
Sets whether debugging output will be printed.
- Parameters:
debug
- true if debugging output should be printed
getDebug
public boolean getDebug()
Gets whether debugging output will be printed.
- Returns:
- true if debugging output will be printed
buildClassifier
public void buildClassifier(Instances train) throws java.lang.Exception
Builds the classifier
- Parameters:
data
- the training data to be used for generating the
boosted classifier.
- Throws:
- java.lang.Exception - if the classifier could not be built successfully
- Overrides:
- buildClassifier in class Classifier
distributionForInstance
public double[] distributionForInstance(Instance instance) throws java.lang.Exception
Computes the distribution for a given instance
- Parameters:
instance
- the instance for which distribution is computed
- Returns:
- the distribution
- Throws:
- java.lang.Exception - if the distribution can't be computed successfully
- Overrides:
- distributionForInstance in class DistributionClassifier
toString
public java.lang.String toString()
Gets a string describing the classifier.
- Returns:
- a string describing the classifer built.
- Overrides:
- toString in class java.lang.Object
main
public static void main(java.lang.String argv[])
Main method for testing this class.
- Parameters:
argv
- should contain the command line arguments to the
scheme (see Evaluation)
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