In the years since Dr. Deming’s passing, much has been made about the "new wave" of quality methodology, Six Sigma. This paper will compare and contrast Dr. Deming’s philosophy with that of the Six Sigma approach by describing the commonalities, differences, and the effectiveness of each.
There is much confusion, it seems,over the meanings of these concepts. Any meaningful discussion must begin with an understanding of how the author is using the terms.
Dr. W. Edwards Deming was a prolific writer in the fields of mathematical physics, statistics, and finally, management philosophy. This paper will primarily consider the "management philosophy" portion of Dr. Deming’s teaching.
Themanagement philosophy of Dr. Deming can probably best be summarized by two major components: Profound Knowledge and the Fourteen Points. Dr. Deming’s Fourteen Points (and their partners, the Seven Deadly Diseases) first appeared in print in the landmark publication Out of the Crisis in 1986. The Fourteen Points are a collection of advice, warnings, and admonishments for management to use to improve theirbusiness.
A more cohesive theory, A System of Profound Knowledge, is presented in The New Economics,(Deming, 1994) and, according to Dr. Deming, "…provides a map of theory by which to understand the organizations that we work in." It is supported by four major tenets: Appreciation of a System, Theory of Knowledge, Theory of Variation, and Psychology. Many themes that are echoes of the FourteenPoints show up in various parts of the System of Profound Knowledge, particularly those relating to organizational purpose, driving out fear in an organization, and understanding the implications of variation.
Systems theory describes ways in which management can turn their organization into a system, and the advantages of doing so. Optimization of parts of the system results insub-optimization of the system. Dr. Deming’s writings describe as well many obstacles to creation of an organizational system, such as incentives for performance of one aspect of the system, internal competition, and the use of the performance appraisal.
The Theory of Knowledge describes a system for learning, and the importance and use of theory to promote learning. Deming presents the latest version of theShewhart cycle, the Plan-Do-Study-Act (PDSA) cycle as a model for achieving this goal.
The Theory of Variation describes the need for management to understand variation, and to use this understanding to improve processes and systems. Deming describes management itself as primarily prediction, and an understanding of variation is critical to being able to predict, to separate the signal fromthe noise, the "common cause" variation from the "special cause" variation.
Psychology comes into play in all aspects of the System of Profound Knowledge model. Management must be aware of underlying psychological influences if the business is ever to approach becoming a true system.
The various definitions of "Six Sigma Quality"
Two of the major advocates of Six Sigma, Dr. Mikel Harry andRichard Schroeder, define the term in this way: "… a business process that allows companies to drastically improve their bottom line by designing and monitoring everyday business activities in ways that minimize waste and resources while increasing customer satisfaction." Further amplification is provided in their book, Six Sigma: The Breakthrough Management Strategy Revolutionizing the World’sTop Corporations (Harry & Schroeder, 1999). Six Sigma is referenced as "… a disciplined method of using extremely rigorous data gathering and statistical analysis to pinpoint sources of errors and ways of eliminating them." As described in the book, a Six Sigma project will follow the principles of RDMAICSI: Recognize, Define, Measure, Analyze, Improve, Control, Standardize, and Integrate. Similar...