List of usage examples for org.apache.commons.math3.linear ArrayRealVector outerProduct
@Override
public RealMatrix outerProduct(RealVector v)
From source file:edu.cudenver.bios.power.glmm.GLMMTestUnirepGeisserGreenhouse.java
/** * Calculate the Geisser-Greenhouse epsilon to correct for violations * of sphericity/*from w w w . jav a2 s .c o m*/ */ @Override protected void calculateEpsilon() { super.calculateEpsilon(); if (this.epsilonMethod == UnivariateEpsilonApproximation.MULLER_BARTON_APPROX) { // calculate the expected value of the epsilon estimate // E[f(lambda)] = f(lambda) + g1 / (N - r) // see Muller, Barton (1989) for details double b = rankU; double g1 = 0; for (int i = 0; i < distinctSigmaStarEigenValues.size(); i++) { EigenValueMultiplicityPair evmI = distinctSigmaStarEigenValues.get(i); double firstDerivative = ((2 * sumLambda) / (b * sumLambdaSquared) - (2 * evmI.eigenValue * sumLambda * sumLambda) / (b * sumLambdaSquared * sumLambdaSquared)); double secondDerivative = (2 / (b * sumLambdaSquared) - (8 * evmI.eigenValue * sumLambda) / (b * sumLambdaSquared * sumLambdaSquared) + (8 * evmI.eigenValue * evmI.eigenValue * sumLambda * sumLambda) / (b * sumLambdaSquared * sumLambdaSquared * sumLambdaSquared) - (2 * sumLambda * sumLambda) / (b * sumLambdaSquared * sumLambdaSquared)); // accumulate the first term of g1 (sum over distinct eigen vals of 1st derivative * eigen val ^2 * multiplicity) g1 += secondDerivative * evmI.eigenValue * evmI.eigenValue * evmI.multiplicity; // loop over elements not equal to current for (int j = 0; j < distinctSigmaStarEigenValues.size(); j++) { if (i != j) { EigenValueMultiplicityPair evmJ = distinctSigmaStarEigenValues.get(j); // accumulate second term of g1 g1 += ((firstDerivative * evmI.eigenValue * evmI.multiplicity * evmJ.eigenValue * evmJ.multiplicity) / (evmI.eigenValue - evmJ.eigenValue)); } } } expectedEpsilon = epsilonD + g1 / (totalN - rank); } else { // calculate the expected value of the epsilon estimate // see Muller, Edwards, Taylor (2004) for details // build a vector with each eigen value repeated per its multiplicity ArrayRealVector eigenColumnVector = new ArrayRealVector(); for (EigenValueMultiplicityPair evmp : distinctSigmaStarEigenValues) { // there is probably a more memory-efficient method to do this. eigenColumnVector = eigenColumnVector .append(new ArrayRealVector((int) evmp.multiplicity, evmp.eigenValue)); } RealMatrix outerProduct = eigenColumnVector.outerProduct(eigenColumnVector); double sum = outerProduct.walkInOptimizedOrder(new SummationVisitor()); double nu = (totalN - rank); double expT1 = (2 * nu * sumLambdaSquared) + (nu * nu * sumLambda * sumLambda); double expT2 = (nu * (nu + 1) * sumLambdaSquared) + (nu * sum * sum); expectedEpsilon = (1 / (double) rankU) * (expT1 / expT2); } // ensure that expected value is within bounds 1/b to 1 if (!Double.isNaN(expectedEpsilon)) { if (expectedEpsilon < 1 / rankU) { expectedEpsilon = 1 / rankU; } else if (expectedEpsilon > 1) { expectedEpsilon = 1; } } }