Why are data from any measurable characteristic that fail to demonstrate control, not operating predictably and, therefore, contribute to decisions that are economically and strategically suspect?
Conceptual Pattern for Control
Control is the ability to purposefully direct, or suppress, change through regulation or maintain a function or action to keep something at the correct level. The act of control brings something to uniformity by bringing to a position of stability on a scale of intensity as a variance from a routine or pattern. Control establishes a state of being governed by official rules in a range of relative scales or values when they can be counted or measured that makes something different when something passes from one state or phase to another. (Pattern Engine – Control N=12 © 2014)
If control is understood then the meaning of Quality will follow.
First Principle: The purpose of control is to assure the predictability and usefulness of data streams.
Second Principle: A phenomenon will be said to be controlled when, through past experience, we can predict, at least within limits, how the phenomenon may be expected to vary in the future.1
Third Principle: A process will be said to be predictable when, through the use of past experience, we can describe, at least within limits how the process will behave in the future.1
Fourth Principle: Control is characterized by a stable and consistent pattern of variation overtime.2
Fifth Principle: Samples drawn from an out of control process are economically and strategically suspect.
Sixth Principle: Statistical Process Control is a way of thinking with some tools attached. 2
Key Conceptual Patterns
Stability is resistance to a changed position or variation resulting in a condition of being in equilibrium. Stability occurs when something passes from one state or phase to another and by which things become different by varying from a routine or pattern and are not be affected by a particular treatment. Stability tends to retard or oppose change leading to all acting forces balancing each other out. (Pattern Engine – Stability N=12 © 2014)
A pattern is a general concept formed by extracting common features from specific examples. Patterns are distinct and unifying ideas that are simplified versions of something complex. They are used in analyzing and solving problems, making predictions or making a comparison that is perceived as an entity. A pattern is a recurrent idea expanded in a discourse due to a special set of circumstances. They are considered as a whole, belong together, referred to by name and serve as a master from which other similar things can be made, copied, or used as the basis for a related idea, process, or system. (Pattern Engine – Pattern N=12 © 2013)
1 Walter Shewhart, Economic Control of Quality of Manufactured Product, 1931.
2 Donald J. Wheeler, Understanding Variation – The Key to Managing Chaos, 2000.