Glossary “U” Definition of Terms in DataMyte

u-Chart

For attribute data: a control chart of the average number of defects per part in a subgroup. 

UCL (Upper Control Limit)

For control charts: the upper limit below which a process remains if it is in control. 

Uniform Distribution

This distribution means that all outcomes are equally likely. 

Unit of Measure

The smallest increment a measurement system can indicate. See also Resolution. 

Universe

The population or universe represents the entire group of units which is the focus of the study

See also Population. 

USL (Upper Specification Limit)

The highest value of a product dimension or measurement that is acceptable.