Definitionv1
Common-cause variation: the inherent, natural fluctuation
Common-cause variation: the inherent, natural fluctuation within a stable system that produces normal performance variations without requiring investigation or intervention, distinguishable from special-cause variation through trend analysis.
Why This Is a Definition
This definition precisely establishes 'common-cause variation' by naming it, identifying its genus (type of variation), and differentiating it through its differentia (inherent, natural, requiring no intervention). It's specific enough to distinguish from 'special-cause variation' and aligns with Shewhart's statistical process control framework as presented in the curriculum.