Common Cause Variation is a type of variation which is natural and inherent to a process. Common Causes act randomly and independently of each other, are difficult to eliminate, and often require changes to a process or system.
The output of Common Cause variation generally conforms to a normal distribution and is stable over the time. Contrast this to Special Cause Variation, which often manifests as an outlier, shift, trend or some other signal on a graph and is therefore easier to identify and fix without significant modifications to a system.
For a better understanding of Common Cause Variation and an overview of Lean Six Sigma, check out our Free Lean Six Sigma Yellow Belt Training, Green Belt Training or Lean Training.
