Get Stats on your Data
QW6 performs over 50 separate statistical calculations on your data and displays the results in the Statistics Box of the individual QW6 Views & Charts.
Review the table below that shows all the statistics that QW6 calculates on your data.
| Statistic | Abbr. | Explanation |
|---|---|---|
| Number of Points | N | The number of non-null values found in the data selected. |
| Target Deviation | T-Dev | The separation between the average and the Target value of the variable. |
| Standard Deviation – Population | S‑pop | The square root of the average of the squared distances of the observations from the mean. |
| Current Standard Deviation | C‑SD | The square root of the average of the squared distances of the observations from the mean based on the current Limit Method. |
| Standard Deviation – Low | SD‑low | The lowest segmented SD over a given range of data values. |
| Standard Deviation – Moving Range | SD‑mr | ((Moving Range Average * 3.267) – Moving Range Average)/3 |
| Maximum | Max | The greatest value of the selected data. This value will highlight if the maximum value exceeds the specification limits for the variable. |
| Upper Specification Limit | USL | Average of all data points plus +4 X the selected SD method |
| Upper Process Capability Limit | UPCL | Average of all data points plus +3 X the selected SD method |
| Upper Warning Limit | UWL | Average of all data points plus +1.5 X the selected SD method |
| Average | AVG | The mathematical average of all data points selected. |
| Current Average | C‑AVG | The mathematical average of all data points selected based on the current Limit Method. |
| Lower Warning Limit | LWL | Average of all data points less -1.5 X the selected SD method |
| Lower Process Capability Limit | LPCL | Average of all data points less -3 X the selected SD method |
| Lower Specification Limit | LSL | Average of all data points less -4 X the selected SD method |
| Minimum | Min | The lowest value of the selected data. This value will highlight if the maximum value exceeds the specification limits for the variable. |
| Median | Med | The middle value of the data set, once numerically sorted. |
| Obs % OSL | O % OSL | The percentage of points outside of fixed spec limits. |
| Obs ppm OSL | O ppm OSL | The number of points outside of fixed spec limits, expressed in parts per million. |
| Calc % OSL | C % OSL | The percentage of points outside of +/- 4SD under the normal curve. |
| Calc ppm OSL | C ppm OSL | The number of points outside of +/- 4SD under the normal curve, expressed in parts per million. |
| Variation | Cr | The capability ratio describes the size of the process variability relative to the size of the specification range. |
| Targeting | Tz | This is determined by dividing the standard deviation into the Target Deviation. This produces a number that measures how well the process is centered on target in standard deviations. |
| Clearance | Cpk | Capability Clearance describes the clearance between the process distribution curve and the specification limits in terms of standard deviation. |
| Coefficient Variation | %CV | SD divided by average – used to normalize SD so it can be compared to other variables. |
| Moving Range Average | MR‑AVG | Average of range between all data points. |
| Moving Range UCL | MR‑UCL | +3 X Moving Range Standard Deviation |
| Moving Range UWL | MR‑UWL | +1.5 X Moving Range Standard Deviation |
| Moving Range LWL | MR‑LWL | -1.5 X Moving Range Standard Deviation |
| Rule Violation | Rule | Alarms based on limits or consecutive data points. |
| Sum | Sum | The total of all data points for a variable. |
| Last Value | LV | The last non-null value for the currently selected variable. |