Class IndTestCramerT

java.lang.Object
edu.cmu.tetrad.search.work_in_progress.IndTestCramerT
All Implemented Interfaces:
IndependenceTest

public final class IndTestCramerT extends Object implements IndependenceTest
Checks conditional independence for continuous variables using Cramer's T-test formula (Cramer, Mathematical Methods of Statistics (1951), page 413).
Author:
josephramsey
  • Constructor Details

    • IndTestCramerT

      public IndTestCramerT(DataSet dataSet, double alpha)
      Constructs a new Independence test which checks independence facts based on the correlation matrix implied by the given data set (must be continuous). The given significance level is used.
      Parameters:
      dataSet - A data set with all continuous columns.
      alpha - the alpha level of the test.
    • IndTestCramerT

      public IndTestCramerT(CorrelationMatrix covMatrix, double alpha)
      Constructs a new independence test that will determine conditional independence facts using the given correlation matrix and the given significance level.
    • IndTestCramerT

      public IndTestCramerT(ICovarianceMatrix covMatrix, double alpha)
      Constructs a new independence test that will determine conditional independence facts using the given correlation matrix and the given significance level.
  • Method Details

    • indTestSubset

      public IndependenceTest indTestSubset(List<Node> vars)
      Creates a new IndTestCramerT instance for a subset of the variables.
      Specified by:
      indTestSubset in interface IndependenceTest
      Parameters:
      vars - The sublist of variables.
    • checkIndependence

      public IndependenceResult checkIndependence(Node x, Node y, Set<Node> _z)
      Determines whether variable x is independent of variable y given a list of conditioning variables z.
      Specified by:
      checkIndependence in interface IndependenceTest
      Parameters:
      x - the one variable being compared.
      y - the second variable being compared.
      _z - the list of conditioning variables.
      Returns:
      true iff x _||_ y | z.
      Throws:
      RuntimeException - if a matrix singularity is encountered.
      See Also:
    • getPValue

      public double getPValue()
      Returns:
      the probability associated with the most recently computed independence test.
    • getAlpha

      public double getAlpha()
      Description copied from interface: IndependenceTest
      Returns the significance level of the independence test.
      Specified by:
      getAlpha in interface IndependenceTest
      Returns:
      the getModel significance level.
    • setAlpha

      public void setAlpha(double alpha)
      Sets the significance level for future tests.
      Specified by:
      setAlpha in interface IndependenceTest
      Parameters:
      alpha - This level.
    • getVariables

      public List<Node> getVariables()
      Specified by:
      getVariables in interface IndependenceTest
      Returns:
      the list of variables over which this independence checker is capable of determinine independence relations-- that is, all the variables in the given graph or the given data set.
    • determines

      public boolean determines(List<Node> z, Node x) throws UnsupportedOperationException
      Returns:
      the variable with the given name, or null if there is no such variable.
      Throws:
      UnsupportedOperationException
    • getData

      public DataSet getData()
      Specified by:
      getData in interface IndependenceTest
      Returns:
      The data model for the independence test, either a DataSet or a CovarianceMatrix.
      See Also:
    • toString

      public String toString()
      Description copied from interface: IndependenceTest
      Returns a string representation of this test.
      Specified by:
      toString in interface IndependenceTest
      Overrides:
      toString in class Object
      Returns:
      a string representation of this test.
    • isVerbose

      public boolean isVerbose()
      Description copied from interface: IndependenceTest
      Returns true if the test prints verbose output.
      Specified by:
      isVerbose in interface IndependenceTest
      Returns:
      True if the case.
    • setVerbose

      public void setVerbose(boolean verbose)
      Description copied from interface: IndependenceTest
      Sets whether this test will print verbose output.
      Specified by:
      setVerbose in interface IndependenceTest
      Parameters:
      verbose - True, if so.