Ejemplo n.º 1
0
  private double getDerivative(Sextad sextad, Sigma sigma) {
    Node a = sigma.getA();
    Node b = sigma.getB();

    Node n1 = sextad.getI();
    Node n2 = sextad.getJ();
    Node n3 = sextad.getK();
    Node n4 = sextad.getL();
    Node n5 = sextad.getM();
    Node n6 = sextad.getN();

    if (a == n1) {
      if (b == n4) {
        return r(n2, n5) * r(n3, n6) - r(n2, n6) * r(n3, n5);

      } else if (b == n5) {
        return -r(n2, n4) * r(n3, n6) + r(n3, n4) * r(n2, n6);

      } else if (b == n6) {
        return r(n2, n4) * r(n3, n5) - r(n3, n4) * r(n2, n5);
      }

    } else if (a == n2) {
      if (b == n4) {
        return r(n3, n5) * r(n1, n6) - r(n1, n5) * r(n3, n6);

      } else if (b == n5) {
        return r(n1, n4) * r(n3, n6) - r(n3, n4) * r(n1, n6);

      } else if (b == n6) {
        return -r(n1, n4) * r(n3, n5) + r(n3, n4) * r(n1, n5);
      }

    } else if (a == n3) {
      if (b == n4) {
        return r(n1, n5) * r(n2, n6) - r(n2, n5) * r(n1, n6);

      } else if (b == n5) {
        return -r(n1, n4) * r(n2, n6) + r(n2, n4) * r(n1, n6);

      } else if (b == n6) {
        return r(n1, n4) * r(n2, n5) - r(n2, n4) * r(n1, n5);
      }
    }

    // symmetry
    n6 = sextad.getI();
    n5 = sextad.getJ();
    n4 = sextad.getK();
    n3 = sextad.getL();
    n2 = sextad.getM();
    n1 = sextad.getN();

    if (a == n1) {
      if (b == n4) {
        return r(n2, n5) * r(n3, n6) - r(n2, n6) * r(n3, n5);

      } else if (b == n5) {
        return -r(n2, n4) * r(n3, n6) + r(n3, n4) * r(n2, n6);

      } else if (b == n6) {
        return r(n2, n4) * r(n3, n5) - r(n3, n4) * r(n2, n5);
      }

    } else if (a == n2) {
      if (b == n4) {
        return r(n3, n5) * r(n1, n6) - r(n1, n5) * r(n3, n6);

      } else if (b == n5) {
        return r(n1, n4) * r(n3, n6) - r(n3, n4) * r(n1, n6);

      } else if (b == n6) {
        return -r(n1, n4) * r(n3, n5) + r(n3, n4) * r(n1, n5);
      }

    } else if (a == n3) {
      if (b == n4) {
        return r(n1, n5) * r(n2, n6) - r(n2, n5) * r(n1, n6);

      } else if (b == n5) {
        return -r(n1, n4) * r(n2, n6) + r(n2, n4) * r(n1, n6);

      } else if (b == n6) {
        return r(n1, n4) * r(n2, n5) - r(n2, n4) * r(n1, n5);
      }
    }

    return 0.0;
  }
Ejemplo n.º 2
0
  /**
   * Takes a list of tetrads for the given data set and returns the chi square value for the test.
   * We assume that the tetrads are non-redundant; if not, a matrix exception will be thrown.
   *
   * <p>Calculates the T statistic (Bollen and Ting, p. 161). This is significant if tests as
   * significant using the Chi Square distribution with degrees of freedom equal to the number of
   * nonredundant tetrads tested.
   */
  @Override
  //    public double calcChiSquare1(Sextad... sextads) {
  //        this.storedSextads = sextads;
  //
  //        this.df = sextads.length;
  //
  //        // Need a list of symbolic covariances--i.e. covariances that appear in tetrads.
  //        Set<Sigma> boldSigmaSet = new LinkedHashSet<Sigma>();
  //        List<Sigma> boldSigma = new ArrayList<Sigma>();
  //
  //        for (Sextad sextad : sextads) {
  //            boldSigmaSet.add(new Sigma(sextad.getI(), sextad.getL()));
  //            boldSigmaSet.add(new Sigma(sextad.getI(), sextad.getM()));
  //            boldSigmaSet.add(new Sigma(sextad.getI(), sextad.getN()));
  //
  //            boldSigmaSet.add(new Sigma(sextad.getJ(), sextad.getL()));
  //            boldSigmaSet.add(new Sigma(sextad.getJ(), sextad.getM()));
  //            boldSigmaSet.add(new Sigma(sextad.getJ(), sextad.getN()));
  //
  //            boldSigmaSet.add(new Sigma(sextad.getK(), sextad.getL()));
  //            boldSigmaSet.add(new Sigma(sextad.getK(), sextad.getM()));
  //            boldSigmaSet.add(new Sigma(sextad.getK(), sextad.getN()));
  //        }
  //
  //        for (Sigma sigma : boldSigmaSet) {
  //            boldSigma.add(sigma);
  //        }
  //
  //        // Need a matrix of variances and covariances of sample covariances.
  //        TetradMatrix sigma_ss = TetradMatrix.instance(boldSigma.size(), boldSigma.size());
  //
  //        for (int i = 0; i < boldSigma.size(); i++) {
  //            for (int j = 0; j < boldSigma.size(); j++) {
  //                Sigma sigmaef = boldSigma.get(i);
  //                Sigma sigmagh = boldSigma.get(j);
  //
  //                Node e = sigmaef.getA();
  //                Node f = sigmaef.getB();
  //                Node g = sigmagh.getA();
  //                Node h = sigmagh.getB();
  //
  //                if (cov != null && cov instanceof CorrelationMatrix) {
  //
  ////                Assumes multinormality. Using formula 23. (Not implementing formula 22 because
  // that case
  ////                does not come up.)
  //                    double rr = 0.5 * (r(e, f) * r(g, h))
  //                            * (r(e, g) * r(e, g) + r(e, h) * r(e, h) + r(f, g) * r(f, g) + r(f,
  // h) * r(f, h))
  //                            + r(e, g) * r(f, h) + r(e, h) * r(f, g)
  //                            - r(e, f) * (r(f, g) * r(f, h) + r(e, g) * r(e, h))
  //                            - r(g, h) * (r(f, g) * r(e, g) + r(f, h) * r(e, h));
  //
  //                    sigma_ss.set(i, j, rr);
  //                } else if (cov != null && dataSet == null) {
  //
  //                    // Assumes multinormality--see p. 160.
  //                    double _ss = r(e, g) * r(f, h) + r(e, h) * r(f, g);   // + or -? Different
  // advise. + in the code.
  //                    sigma_ss.set(i, j, _ss);
  //                } else {
  //                    double _ss = sxyzw(e, f, g, h) - r(e, f) * r(g, h);
  //                    sigma_ss.set(i, j, _ss);
  //                }
  //            }
  //        }
  //
  //        // Need a matrix of of population estimates of partial derivatives of tetrads
  //        // with respect to covariances in boldSigma.
  //        TetradMatrix del = TetradMatrix.instance(boldSigma.size(), sextads.length);
  //
  //        for (int i = 0; i < boldSigma.size(); i++) {
  //            for (int j = 0; j < sextads.length; j++) {
  //                Sigma sigma = boldSigma.get(i);
  //                Sextad sextad = sextads[j];
  //
  //                Node m1 = sextad.getI();
  //                Node m2 = sextad.getJ();
  //                Node m3 = sextad.getK();
  //                Node m4 = sextad.getL();
  //                Node m5 = sextad.getM();
  //                Node m6 = sextad.getN();
  //
  //                double derivative = getDerivative(m1, m2, m3, m4, m5, m6, sigma.getA(),
  // sigma.getB());
  //                del.set(i, j, derivative);
  //            }
  //        }
  //
  //        // Need a vector of population estimates of the sextads.
  //        TetradMatrix t = TetradMatrix.instance(sextads.length, 1);
  //
  //        for (int i = 0; i < sextads.length; i++) {
  //            Sextad sextad = sextads[i];
  //
  //            List<Node> nodes = new ArrayList<Node>();
  //
  //            nodes.add(sextad.getI());
  //            nodes.add(sextad.getJ());
  //            nodes.add(sextad.getK());
  //            nodes.add(sextad.getL());
  //            nodes.add(sextad.getM());
  //            nodes.add(sextad.getN());
  //
  //            TetradMatrix m = TetradMatrix.instance(3, 3);
  //
  //            for (int k1 = 0; k1 < 3; k1++) {
  //                for (int k2 = 0; k2 < 3; k2++) {
  //                    m.set(k1, k2, r(nodes.get(k1), nodes.get(3+k2)));
  //                }
  //            }
  //
  //            double value = TetradAlgebra.det(m);
  //            t.set(i, 0, value);
  //            this.storedValue = value;
  //        }
  //
  //        // Now multiply to get Sigma_tt
  //        TetradMatrix w1 = TetradAlgebra.times(del.transpose(), sigma_ss);
  //        TetradMatrix sigma_tt = TetradAlgebra.times(w1, del);
  //
  //        // And now invert and multiply to get T.
  //        TetradMatrix v0 = TetradAlgebra.inverse(sigma_tt);
  //        TetradMatrix v1 = TetradAlgebra.times(t.transpose(), v0);
  //        TetradMatrix v2 = TetradAlgebra.times(v1, t);
  //        double chisq = N * v2.get(0, 0);
  //
  //        this.chisq = chisq;
  //        return chisq;
  //    }
  public double calcChiSquare(Sextad... sextads) {
    this.storedSextads = sextads;

    this.df = 4; // sextads.length;

    List<Sigma> boldSigma = new ArrayList<Sigma>();

    List<Node> _nodes = new ArrayList<Node>(sextads[0].getNodes());

    for (int i = 0; i < _nodes.size(); i++) {
      for (int j = i + 1; j < _nodes.size(); j++) {
        boldSigma.add(new Sigma(_nodes.get(i), _nodes.get(j)));
      }
    }

    // Need a matrix of variances and covariances of sample covariances.
    TetradMatrix sigma_ss = new TetradMatrix(boldSigma.size(), boldSigma.size());

    for (int i = 0; i < boldSigma.size(); i++) {
      for (int j = i; j < boldSigma.size(); j++) {
        Sigma sigmaef = boldSigma.get(i);
        Sigma sigmagh = boldSigma.get(j);

        Node e = sigmaef.getA();
        Node f = sigmaef.getB();
        Node g = sigmagh.getA();
        Node h = sigmagh.getB();

        if (cov != null && cov instanceof CorrelationMatrix) {

          //                Assumes multinormality. Using formula 23. (Not implementing formula 22
          // because that case
          //                does not come up.)
          double rr =
              0.5
                      * (r(e, f) * r(g, h))
                      * (r(e, g) * r(e, g)
                          + r(e, h) * r(e, h)
                          + r(f, g) * r(f, g)
                          + r(f, h) * r(f, h))
                  + r(e, g) * r(f, h)
                  + r(e, h) * r(f, g)
                  - r(e, f) * (r(f, g) * r(f, h) + r(e, g) * r(e, h))
                  - r(g, h) * (r(f, g) * r(e, g) + r(f, h) * r(e, h));

          sigma_ss.set(i, j, rr);
          sigma_ss.set(j, i, rr);
        } else if (cov != null && dataSet == null) {

          // Assumes multinormality--see p. 160.
          double _ss =
              r(e, g) * r(f, h) + r(e, h) * r(f, g); // + or -? Different advise. + in the code.
          //                    double _ss = r(e, g) * r(f, h) - r(e, h) * r(g, f);   // shouldn't
          // this be a tetrad?
          sigma_ss.set(i, j, _ss);
          sigma_ss.set(j, i, _ss);
        } else {
          double _ss = sxyzw(e, f, g, h) - r(e, f) * r(g, h);
          sigma_ss.set(i, j, _ss);
          sigma_ss.set(j, i, _ss);
        }
      }
    }

    // Need a matrix of of population estimates of partial derivatives of tetrads
    // with respect to covariances in boldSigma.
    TetradMatrix del = new TetradMatrix(boldSigma.size(), sextads.length);

    for (int j = 0; j < sextads.length; j++) {
      Sextad sextad = sextads[j];

      for (int i = 0; i < boldSigma.size(); i++) {
        Sigma sigma = boldSigma.get(i);
        double derivative = getDerivative(sextad, sigma);
        del.set(i, j, derivative);
      }
    }

    // Need a vector of population estimates of the sextads.
    TetradMatrix t = new TetradMatrix(sextads.length, 1);

    for (int i = 0; i < sextads.length; i++) {
      Sextad sextad = sextads[i];
      List<Node> nodes = sextad.getNodes();
      TetradMatrix m = new TetradMatrix(3, 3);

      for (int k1 = 0; k1 < 3; k1++) {
        for (int k2 = 0; k2 < 3; k2++) {
          m.set(k1, k2, r(nodes.get(k1), nodes.get(3 + k2)));
        }
      }

      double det = m.det();
      t.set(i, 0, det);
      this.storedValue = det; // ?
    }

    //        for (int i = 0; i < sextads.length; i++) {
    //            Sextad sextad = sextads[i];
    //
    //            List<Node> nodes = new ArrayList<Node>();
    //
    //            nodes.add(sextad.getI());
    //            nodes.add(sextad.getJ());
    //            nodes.add(sextad.getK());
    //            nodes.add(sextad.getL());
    //            nodes.add(sextad.getM());
    //            nodes.add(sextad.getN());
    //
    //            TetradMatrix m = TetradMatrix.instance(3, 3);
    //
    //            for (int k1 = 0; k1 < 3; k1++) {
    //                for (int k2 = 0; k2 < 3; k2++) {
    //                    m.set(k1, k2, r(nodes.get(k1), nodes.get(3+k2)));
    //                }
    //            }
    //
    //            double value = TetradAlgebra.det(m);
    //            t.set(i, 0, value);
    //            this.storedValue = value;
    //        }

    TetradMatrix sigma_tt = del.transpose().times(sigma_ss).times(del);
    try {
      this.chisq = N * t.transpose().times(sigma_tt.inverse()).times(t).get(0, 0);
      return chisq;
    } catch (Exception e) {
      return Double.NaN;
    }
  }