R-Chart A control chart based on the range (R) of a subgroup, typically used in conjunction with an x-bar chart.
Run A consecutive number of points consistently increasing or decreasing, or above or below the center line. A run can be evidence of the existence of special causes of variation that should be investigated.
Runs Chart A simple graphic representation of a characteristic of a process which shows plotted values of some statistic gathered from the process. The graphic can be analyzed for trends or other unusual patterns.
Range A measure of the spread of the data, calculated as highest value minus lowest value. Range = R = xmax – xmin