Quality Window performs over 50 separate statisical calculations on your data, and displays the results in the Statistics Box. These results can also be copied to the Windows clipboard and pasted into Excel®, Microsoft Word, or any other program.
| Statistic |
Abbrev. |
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. |
