When is it used?
Run charts are often used with baseline data at the beginning of a project. If you do not have enough data for control limits, SQCpack let you switch the control chart display to a run chart and switch back when you have enough data.
Use run charts when you can answer yes to these questions:
- Is the data collected over time?
- Is the time order of the data preserved?
Getting the most
Run charts should be used as a quick test of system performance. Start ups and short runs in manufacturing settings often produce too little data for conventional control chart analysis, but are easily analyzed in a run chart. Inspection data generated in these situations should be plotted immediately on a run chart to enable quick diagnosis of system changes over time or to identify signs that the process has begun to stabilize.
Run charts are good way to illustrate and share information with other departments. They are often used to post sales figures for all to see. Patterns and trends are much easier to see on a run chart than in a matrix of rows and columns.
Because run charts can be easily constructed, they are especially useful for one-time analysis of historical data.