Theory …

Understanding Variation tackles a very common condition that affects most people in the “Information Age” – numerical illiteracy. This is the difficulty we have with digesting data to extract the knowledge that may be locked up inside. Unfortunately numerical illiteracy is not prevented by traditional primary, secondary or even higher education – and even highly intelligent and capable individuals can still be numerically illiterate. Fortunately, an  effective treatment is available: one that has been thoroughly proven in over 60 years of use in all walks of life - the process behaviour chart.

First Principle for Understanding Data
No data have meaning apart from their context.

Second Principle for Understanding Data
While every data set contains noise, some data sets may contain signals. Therefore, before you can detect a signal within any given data set, you must first filter out the noise.

Equipped with the knowledge of how easy it is to create a process behaviour chart, all you need is some practice to rid yourself of the disabling condition of numerical illiteracy – and the real world offers ample opportunities for practice!