This example uses stratified cross-validation to select parameter settings for C and using the minimum CV error criterion. Then, the fitted model using the "best" settings is used to classify the entire dataset. The classification errors are shown.
import com.imsl.datamining.*; import com.imsl.datamining.supportvectormachine.*; import com.imsl.datamining.neural.*; import com.imsl.stat.*; public class SupportVectorMachineEx2 { public static void main(String[] args) throws Exception { SVClassification.VariableType[] irisVarType = { SVClassification.VariableType.CATEGORICAL, SVClassification.VariableType.QUANTITATIVE_CONTINUOUS, SVClassification.VariableType.QUANTITATIVE_CONTINUOUS, SVClassification.VariableType.QUANTITATIVE_CONTINUOUS, SVClassification.VariableType.QUANTITATIVE_CONTINUOUS }; String dashes = "--------------------------------------------------------------"; double[][] irisFisherData = { {1.0, 5.1, 3.5, 1.4, .2}, {1.0, 4.9, 3.0, 1.4, .2}, {1.0, 4.7, 3.2, 1.3, .2}, {1.0, 4.6, 3.1, 1.5, .2}, {1.0, 5.0, 3.6, 1.4, .2}, {1.0, 5.4, 3.9, 1.7, .4}, {1.0, 4.6, 3.4, 1.4, .3}, {1.0, 5.0, 3.4, 1.5, .2}, {1.0, 4.4, 2.9, 1.4, .2}, {1.0, 4.9, 3.1, 1.5, .1}, {1.0, 5.4, 3.7, 1.5, .2}, {1.0, 4.8, 3.4, 1.6, .2}, {1.0, 4.8, 3.0, 1.4, .1}, {1.0, 4.3, 3.0, 1.1, .1}, {1.0, 5.8, 4.0, 1.2, .2}, {1.0, 5.7, 4.4, 1.5, .4}, {1.0, 5.4, 3.9, 1.3, .4}, {1.0, 5.1, 3.5, 1.4, .3}, {1.0, 5.7, 3.8, 1.7, .3}, {1.0, 5.1, 3.8, 1.5, .3}, {1.0, 5.4, 3.4, 1.7, .2}, {1.0, 5.1, 3.7, 1.5, .4}, {1.0, 4.6, 3.6, 1.0, .2}, {1.0, 5.1, 3.3, 1.7, .5}, {1.0, 4.8, 3.4, 1.9, .2}, {1.0, 5.0, 3.0, 1.6, .2}, {1.0, 5.0, 3.4, 1.6, .4}, {1.0, 5.2, 3.5, 1.5, .2}, {1.0, 5.2, 3.4, 1.4, .2}, {1.0, 4.7, 3.2, 1.6, .2}, {1.0, 4.8, 3.1, 1.6, .2}, {1.0, 5.4, 3.4, 1.5, .4}, {1.0, 5.2, 4.1, 1.5, .1}, {1.0, 5.5, 4.2, 1.4, .2}, {1.0, 4.9, 3.1, 1.5, .1}, {1.0, 5.0, 3.2, 1.2, .2}, {1.0, 5.5, 3.5, 1.3, .2}, {1.0, 4.9, 3.1, 1.5, .1}, {1.0, 4.4, 3.0, 1.3, .2}, {1.0, 5.1, 3.4, 1.5, .2}, {1.0, 5.0, 3.5, 1.3, .3}, {1.0, 4.5, 2.3, 1.3, .3}, {1.0, 4.4, 3.2, 1.3, .2}, {1.0, 5.0, 3.5, 1.6, .6}, {1.0, 5.1, 3.8, 1.9, .4}, {1.0, 4.8, 3.0, 1.4, .3}, {1.0, 5.1, 3.8, 1.6, .2}, {1.0, 4.6, 3.2, 1.4, .2}, {1.0, 5.3, 3.7, 1.5, .2}, {1.0, 5.0, 3.3, 1.4, .2}, {2.0, 7.0, 3.2, 4.7, 1.4}, {2.0, 6.4, 3.2, 4.5, 1.5}, {2.0, 6.9, 3.1, 4.9, 1.5}, {2.0, 5.5, 2.3, 4.0, 1.3}, {2.0, 6.5, 2.8, 4.6, 1.5}, {2.0, 5.7, 2.8, 4.5, 1.3}, {2.0, 6.3, 3.3, 4.7, 1.6}, {2.0, 4.9, 2.4, 3.3, 1.0}, {2.0, 6.6, 2.9, 4.6, 1.3}, {2.0, 5.2, 2.7, 3.9, 1.4}, {2.0, 5.0, 2.0, 3.5, 1.0}, {2.0, 5.9, 3.0, 4.2, 1.5}, {2.0, 6.0, 2.2, 4.0, 1.0}, {2.0, 6.1, 2.9, 4.7, 1.4}, {2.0, 5.6, 2.9, 3.6, 1.3}, {2.0, 6.7, 3.1, 4.4, 1.4}, {2.0, 5.6, 3.0, 4.5, 1.5}, {2.0, 5.8, 2.7, 4.1, 1.0}, {2.0, 6.2, 2.2, 4.5, 1.5}, {2.0, 5.6, 2.5, 3.9, 1.1}, {2.0, 5.9, 3.2, 4.8, 1.8}, {2.0, 6.1, 2.8, 4.0, 1.3}, {2.0, 6.3, 2.5, 4.9, 1.5}, {2.0, 6.1, 2.8, 4.7, 1.2}, {2.0, 6.4, 2.9, 4.3, 1.3}, {2.0, 6.6, 3.0, 4.4, 1.4}, {2.0, 6.8, 2.8, 4.8, 1.4}, {2.0, 6.7, 3.0, 5.0, 1.7}, {2.0, 6.0, 2.9, 4.5, 1.5}, {2.0, 5.7, 2.6, 3.5, 1.0}, {2.0, 5.5, 2.4, 3.8, 1.1}, {2.0, 5.5, 2.4, 3.7, 1.0}, {2.0, 5.8, 2.7, 3.9, 1.2}, {2.0, 6.0, 2.7, 5.1, 1.6}, {2.0, 5.4, 3.0, 4.5, 1.5}, {2.0, 6.0, 3.4, 4.5, 1.6}, {2.0, 6.7, 3.1, 4.7, 1.5}, {2.0, 6.3, 2.3, 4.4, 1.3}, {2.0, 5.6, 3.0, 4.1, 1.3}, {2.0, 5.5, 2.5, 4.0, 1.3}, {2.0, 5.5, 2.6, 4.4, 1.2}, {2.0, 6.1, 3.0, 4.6, 1.4}, {2.0, 5.8, 2.6, 4.0, 1.2}, {2.0, 5.0, 2.3, 3.3, 1.0}, {2.0, 5.6, 2.7, 4.2, 1.3}, {2.0, 5.7, 3.0, 4.2, 1.2}, {2.0, 5.7, 2.9, 4.2, 1.3}, {2.0, 6.2, 2.9, 4.3, 1.3}, {2.0, 5.1, 2.5, 3.0, 1.1}, {2.0, 5.7, 2.8, 4.1, 1.3}, {3.0, 6.3, 3.3, 6.0, 2.5}, {3.0, 5.8, 2.7, 5.1, 1.9}, {3.0, 7.1, 3.0, 5.9, 2.1}, {3.0, 6.3, 2.9, 5.6, 1.8}, {3.0, 6.5, 3.0, 5.8, 2.2}, {3.0, 7.6, 3.0, 6.6, 2.1}, {3.0, 4.9, 2.5, 4.5, 1.7}, {3.0, 7.3, 2.9, 6.3, 1.8}, {3.0, 6.7, 2.5, 5.8, 1.8}, {3.0, 7.2, 3.6, 6.1, 2.5}, {3.0, 6.5, 3.2, 5.1, 2.0}, {3.0, 6.4, 2.7, 5.3, 1.9}, {3.0, 6.8, 3.0, 5.5, 2.1}, {3.0, 5.7, 2.5, 5.0, 2.0}, {3.0, 5.8, 2.8, 5.1, 2.4}, {3.0, 6.4, 3.2, 5.3, 2.3}, {3.0, 6.5, 3.0, 5.5, 1.8}, {3.0, 7.7, 3.8, 6.7, 2.2}, {3.0, 7.7, 2.6, 6.9, 2.3}, {3.0, 6.0, 2.2, 5.0, 1.5}, {3.0, 6.9, 3.2, 5.7, 2.3}, {3.0, 5.6, 2.8, 4.9, 2.0}, {3.0, 7.7, 2.8, 6.7, 2.0}, {3.0, 6.3, 2.7, 4.9, 1.8}, {3.0, 6.7, 3.3, 5.7, 2.1}, {3.0, 7.2, 3.2, 6.0, 1.8}, {3.0, 6.2, 2.8, 4.8, 1.8}, {3.0, 6.1, 3.0, 4.9, 1.8}, {3.0, 6.4, 2.8, 5.6, 2.1}, {3.0, 7.2, 3.0, 5.8, 1.6}, {3.0, 7.4, 2.8, 6.1, 1.9}, {3.0, 7.9, 3.8, 6.4, 2.0}, {3.0, 6.4, 2.8, 5.6, 2.2}, {3.0, 6.3, 2.8, 5.1, 1.5}, {3.0, 6.1, 2.6, 5.6, 1.4}, {3.0, 7.7, 3.0, 6.1, 2.3}, {3.0, 6.3, 3.4, 5.6, 2.4}, {3.0, 6.4, 3.1, 5.5, 1.8}, {3.0, 6.0, 3.0, 4.8, 1.8}, {3.0, 6.9, 3.1, 5.4, 2.1}, {3.0, 6.7, 3.1, 5.6, 2.4}, {3.0, 6.9, 3.1, 5.1, 2.3}, {3.0, 5.8, 2.7, 5.1, 1.9}, {3.0, 6.8, 3.2, 5.9, 2.3}, {3.0, 6.7, 3.3, 5.7, 2.5}, {3.0, 6.7, 3.0, 5.2, 2.3}, {3.0, 6.3, 2.5, 5.0, 1.9}, {3.0, 6.5, 3.0, 5.2, 2.0}, {3.0, 6.2, 3.4, 5.4, 2.3}, {3.0, 5.9, 3.0, 5.1, 1.8} }; // Create a scaled version of the Iris attribute data. double[][] x = new double[150][4]; double[][] xx = new double[150][4]; // Get the data. for (int i = 0; i < 150; i++) { for (int j = 0; j < 4; j++) { x[i][j] = irisFisherData[i][j + 1]; } } // Scale the data. double realMin = 0.0, realMax = 10.0, targetMin = 0.0, targetMax = 1.0; ScaleFilter scaleFilter = new ScaleFilter(ScaleFilter.BOUNDED_SCALING); scaleFilter.setBounds(realMin, realMax, targetMin, targetMax); for (int i = 0; i < 150; i++) { xx[i] = scaleFilter.encode(x[i]); } // Build a training data set. int nTrain = 30; double[][] xy = new double[nTrain][5]; int ii = 0; // The response variable (Iris Species) is encoded starting in "1". // Here, subtract 1 from the response because the class assumes // 0 based categorical response variable. for (int i = 0; i < 3; i++) { for (int j = 0; j < 10; j++) { xy[ii][0] = irisFisherData[(i * 50) + j][0] - 1; System.arraycopy(xx[(i * 50 + j)], 0, xy[ii], 1, 4); ii++; } } // Construct a Support Vector Machine. SVClassification svm = new SVClassification(xy, 0, irisVarType); double[] gamma = {0.1}; double C = 2.0; double result; double minResult = 10000.0; double bestGamma = 0.0; double bestC = 0.0; CrossValidation svmCV = new CrossValidation(svm); svmCV.setNumberOfSampleFolds(5); svmCV.setRandomObject(new Random(123457)); svmCV.setStratifiedCrossValidation(true); for (int i = 0; i < 10; i++) { for (int j = 0; j < 5; j++) { svm.setRegularizationParameter(C); svm.setKernelParameters(gamma); svmCV.crossValidate(); result = svmCV.getCrossValidatedError(); if (result < minResult) { minResult = result; bestGamma = gamma[0]; bestC = C; } gamma[0] = gamma[0] * 2.0; } gamma[0] = 0.1; C = C * 2.0; } System.out.printf("Best C: %5.0f \n", bestC); System.out.printf("Best gamma: %5.3f \n", bestGamma); System.out.printf("Minimum CV error: %5.3f \n", minResult); svm.setRegularizationParameter(bestC); gamma[0] = bestGamma; svm.setKernelParameters(gamma); // Train the model on the training sample (30 observations). svm.fitModel(); // Classify the entire data set with the fitted model // using the "best" C and gamma parameter values. xy = new double[150][5]; double[] knownClass = new double[150]; for (int i = 0; i < 150; i++) { xy[i][0] = irisFisherData[i][0] - 1; knownClass[i] = xy[i][0]; System.arraycopy(xx[i], 0, xy[i], 1, 4); } double[] predictedClass = svm.predict(xy); int[][] classErrors = svm.getClassErrors(knownClass, predictedClass); System.out.println("\n Iris Classification Error Rates"); System.out.println("\n" + dashes); System.out.println(" Setosa Versicolour Virginica | TOTAL"); System.out.println(" " + classErrors[0][0] + "/" + classErrors[0][1] + " " + classErrors[1][0] + "/" + classErrors[1][1] + " " + classErrors[2][0] + "/" + classErrors[2][1] + " " + classErrors[3][0] + "/" + classErrors[3][1]); System.out.println(dashes); } }
Best C: 64 Best gamma: 1.600 Minimum CV error: 0.000 Iris Classification Error Rates -------------------------------------------------------------- Setosa Versicolour Virginica | TOTAL 0/50 1/50 3/50 4/150 --------------------------------------------------------------Link to Java source.