A graphical display of data that shows the median and upper and lower quartiles, along with extreme points and any outliers.
Capability The amount of variation inherent in a stable process. Capability can be determined using data from control charts and histograms and is often quantified using the Cp and Cpk indices.
A quality control tool used to analyze potential causes of problems in a product or process. It is also called a fishbone diagram or an Ishikawa diagram after its developer.
c-Chart A control chart based on counting the number of defects per constant size subgroup. Also known as a Count of Nonconformities chart. The c-chart is based on the Poisson distribution.
Center Line (CL) The line on the control chart that represents the long-run expected or average value of the quality characteristic.