Múltiplas linhas de regressão jFreeChart

package demo;

import java.awt.*;
import javax.swing.JPanel;
import javax.swing.JTabbedPane;
import org.jfree.chart.ChartPanel;
import org.jfree.chart.JFreeChart;
import org.jfree.chart.axis.NumberAxis;
import org.jfree.chart.plot.XYPlot;
import org.jfree.chart.renderer.xy.XYLineAndShapeRenderer;
import org.jfree.data.function.LineFunction2D;
import org.jfree.data.function.PowerFunction2D;
import org.jfree.data.general.DatasetUtilities;
import org.jfree.data.statistics.Regression;
import org.jfree.data.xy.*;
import org.jfree.ui.ApplicationFrame;
import org.jfree.ui.RefineryUtilities;

public class RegressionDemo1 extends ApplicationFrame
{
        static class DemoPanel extends JPanel
        {

                private XYDataset data1;

                private XYDataset createSampleData1()
                {
                        XYSeries xyseries = new XYSeries("Series 1");
                        xyseries.add(2D, 56.270000000000003D);
                        xyseries.add(3D, 41.32D);
                        xyseries.add(4D, 31.449999999999999D);
                        xyseries.add(5D, 30.050000000000001D);
                        xyseries.add(6D, 24.690000000000001D);
                        xyseries.add(7D, 19.780000000000001D);
                        xyseries.add(8D, 20.940000000000001D);
                        xyseries.add(9D, 16.73D);
                        xyseries.add(10D, 14.210000000000001D);
                        xyseries.add(11D, 12.44D);
                        XYSeriesCollection xyseriescollection = new XYSeriesCollection(xyseries);
                        return xyseriescollection;
                }

                private JTabbedPane createContent()
                {
                        JTabbedPane jtabbedpane = new JTabbedPane();
                        jtabbedpane.add("Linear", createChartPanel1());
                        jtabbedpane.add("Power", createChartPanel2());
                        return jtabbedpane;
                }

                private ChartPanel createChartPanel1()
                {
                        NumberAxis numberaxis = new NumberAxis("X");
                        numberaxis.setAutoRangeIncludesZero(false);
                        NumberAxis numberaxis1 = new NumberAxis("Y");
                        numberaxis1.setAutoRangeIncludesZero(false);
                        XYLineAndShapeRenderer xylineandshaperenderer = new XYLineAndShapeRenderer(false, true);
                        XYPlot xyplot = new XYPlot(data1, numberaxis, numberaxis1, xylineandshaperenderer);
                        double ad[] = Regression.getOLSRegression(data1, 0);
                        LineFunction2D linefunction2d = new LineFunction2D(ad[0], ad[1]);
                        XYDataset xydataset = DatasetUtilities.sampleFunction2D(linefunction2d, 2D, 11D, 100, "Fitted Regression Line");
                        xyplot.setDataset(1, xydataset);
                        XYLineAndShapeRenderer xylineandshaperenderer1 = new XYLineAndShapeRenderer(true, false);
                        xylineandshaperenderer1.setSeriesPaint(0, Color.blue);
                        xyplot.setRenderer(1, xylineandshaperenderer1);
                        JFreeChart jfreechart = new JFreeChart("Linear Regression", JFreeChart.DEFAULT_TITLE_FONT, xyplot, true);
                        ChartPanel chartpanel = new ChartPanel(jfreechart, false);
                        return chartpanel;
                }

                private ChartPanel createChartPanel2()
                {
                        NumberAxis numberaxis = new NumberAxis("X");
                        numberaxis.setAutoRangeIncludesZero(false);
                        NumberAxis numberaxis1 = new NumberAxis("Y");
                        numberaxis1.setAutoRangeIncludesZero(false);
                        XYLineAndShapeRenderer xylineandshaperenderer = new XYLineAndShapeRenderer(false, true);
                        XYPlot xyplot = new XYPlot(data1, numberaxis, numberaxis1, xylineandshaperenderer);
                        double ad[] = Regression.getPowerRegression(data1, 0);
                        PowerFunction2D powerfunction2d = new PowerFunction2D(ad[0], ad[1]);
                        XYDataset xydataset = DatasetUtilities.sampleFunction2D(powerfunction2d, 2D, 11D, 100, "Fitted Regression Line");
                        XYLineAndShapeRenderer xylineandshaperenderer1 = new XYLineAndShapeRenderer(true, false);
                        xylineandshaperenderer1.setSeriesPaint(0, Color.blue);
                        xyplot.setDataset(1, xydataset);
                        xyplot.setRenderer(1, xylineandshaperenderer1);
                        JFreeChart jfreechart = new JFreeChart("Power Regression", JFreeChart.DEFAULT_TITLE_FONT, xyplot, true);
                        ChartPanel chartpanel = new ChartPanel(jfreechart, false);
                        return chartpanel;
                }

                public DemoPanel()
                {
                        super(new BorderLayout());
                        data1 = createSampleData1();
                        add(createContent());
                }
        }


        public RegressionDemo1(String s)
        {
                super(s);
                JPanel jpanel = createDemoPanel();
                getContentPane().add(jpanel);
        }

        public static JPanel createDemoPanel()
        {
                return new DemoPanel();
        }

        public static void main(String args[])
        {
                RegressionDemo1 regressiondemo1 = new RegressionDemo1("Regression Demo 1");
                regressiondemo1.pack();
                RefineryUtilities.centerFrameOnScreen(regressiondemo1);
                regressiondemo1.setVisible(true);
        }
}