Statistical Thinking: Improving Business Performance, Second Edition

Chapter 4

Statistical Engineering

Tactics to Deploy Statistical Thinking

To produce quality, you must have a system to improve it.

—Thomas A. Edison

In this chapter, we discuss statistical engineering in greater detail and illustrate three detailed and specific statistical engineering frameworks to apply the statistical thinking strategy presented in Chapter 2. These are certainly not the only statistical engineering frameworks, but they are broadly applicable and illustrate the types of tactical approaches needed to apply the statistical thinking strategy to real problems. Two of the frameworks emphasize process improvement and are intended to address common-cause variation in processes that are stable but at an unsatisfactory level. One framework emphasizes problem solving and is intended to address special-cause variation (i.e., fixing problems). In different ways, these tactical frameworks use many of the same tools.

The most important learning objective in this chapter is to understand how statistical engineering fits the various tools together to form generic frameworks or overall approaches to process improvement and problem solving. The reader should also be able to explain how these frameworks fit into the overall statistical thinking strategy. This understanding is helpful in planning the rest of the course project. We begin with two process improvement case studies. Using these as examples, we depict one of the process improvement frameworks, indicating which tools ...