XbarS Class

XbarS is an X-bar chart for monitoring a process using sample standard deviations.

For a list of all members of this type, see XbarS Members.

System.Object
   Imsl.Chart2D.AbstractChartNode
      Imsl.Chart2D.ChartNode
         Imsl.Chart2D.Data
            Imsl.Chart2D.QC.ShewhartControlChart
               Imsl.Chart2D.QC.XbarS

public class XbarS : ShewhartControlChart

Thread Safety

Public static (Shared in Visual Basic) members of this type are safe for multithreaded operations. Instance members are not guaranteed to be thread-safe.

Remarks

The control limits are at

$\bar{\bar{x}} + k \frac{\bar{s}}{c_{4,n}\sqrt{n}}$

where $\bar{\bar{x}}$ is the grand mean of all of the observations, n is the sample size, and k is the value of the "ControlLimit" attribute for the limit. Additionally, $c_{4,n}$ is a factor such that $\bar{s}/c_{4,n}$ is an unbiased estimator of the within sample standard deviation.

By default, the chart contains an upper control limit line with k=3, a lower control limit line with k=-3, and a central line equal to $\bar{\bar{x}}$ . Additional control limit lines can be added. The method AddWeco adds control limits with k = -2, -1, 1, 2.

Requirements

Namespace: Imsl.Chart2D.QC

Assembly: ImslCS (in ImslCS.dll)

XbarS Class

Thread Safety

Remarks

Requirements

See Also