I received a recommendation to purchase a book (Process Quality Control, by Ellis Ott) and while searching for reviews of this book, found something called Ott's Rules. These are three simple rules advocated by Dr. Ott in any process control problem:
- use data,
- use graphs, and
- plot data in time sequence.
An elaboration on why these rules make sense can be found in the September 11, 2005 posting of the Statistical and Scientific Thinking blog. While browsing this blog, I found another interesting entry on a different blog: