Moving Range Chart – MR Chart
This type of chart displays the moving range of successive observations. A moving range chart can be used when it is impossible or impractical to collect more than a single data point for each subgroup.
This chart can be paired with an individual chart, which is then called an Individual Moving Range (IR) chart. An individual chart is used to highlight the changes in a variable from a central value, the mean. The moving range chart displays variability among measurements based on the difference between one data point and the next.
To create a Moving Range chart: • In Statit Express QC, click on the “MR” button on the menu bar. • In Statit Custom QC, use the menu selection:
QC Variable charts Moving Range Chart The dialogs lead you through the creation of the chart.
If you have any difficulties, open the Help file using the Help button on the Moving Range Chart dialog, or select Help Contents and find “Moving Range Chart” in the Index.
