CuSumStatus

JMSL Chart Programmer’s Guide

CuSumStatus

CuSumStatus is a tabular or status CuSum chart. The tabular CuSum statistics are

By default, both statistics have initial value zero. The parameter K is the slack value (or allowance or reference value) and μ0 is the expected mean.

The CuSumStatus chart contains two bar charts: a bar chart of

above the x-axis and a bar chart of

below the x-axis. There are also control limits at plus and minus H. The value of H can be set either as an absolute value or as a relative value h. They are related by H = hσ, where σ is the standard deviation. By default, bars which are out-of-control are filled red while in-control bars are green. The data is also plotted on the chart.

The CuSumStatus has a print method to print the

and

values as well as

and

, where

is the number of consecutive periods since

rose above zero.

CuSumStatus Example

This example uses the same data as used for the CuSum and EWMA examples. In this example H = 4σ.

View code file

import com.imsl.chart.*;

import com.imsl.chart.qc.*;

public class SampleCuSumStatus extends JFrameChart {

public SampleCuSumStatus() {

double expectedMean = 10;

double slackValue = 0.5;

Chart chart = getChart();

AxisXY axis = new AxisXY(chart);

CuSumStatus cusumStatus = new CuSumStatus(axis,

SampleEWMA.data, expectedMean, slackValue);

cusumStatus.setRelativeH(4);

cusumStatus.print();

axis.getAxisX().getAxisTitle().setTitle("Sample Number");

axis.getAxisX().getAxisLabel().setTextFormat("0");

axis.getAxisY().getAxisTitle().setTitle("C+ / C-");

axis.getAxisX().setWindow(0, 30);

axis.getAxisX().setAutoscaleInput(0);

cusumStatus.addDataMarkers();

cusumStatus.getDataMarkers().setMarkerSize(0.5);

cusumStatus.getDataMarkers().setMarkerColor(java.awt.Color.blue);

Axis1D axisY = cusumStatus.getDataMarkersAxis().getAxisY();

axisY.getAxisTitle().setTitle("Original Data");

}

public static void main(String argv[]) {

new SampleCuSumStatus().setVisible(true);

}