In this series we have been looking at the principles of DMAIC. Last issue we decomposed Define; this issue we will look at step two, "Measure". In issue 15 we had examined the collection of DMAIC and how they link; now we are gaining knowledge regarding each principle, as individuals.
Step Two: MEASURE
The best way to think of Measure is the collecting of tribal knowledge. The whole purpose of DMAIC is to deliver the "Red X's" to the Improvement Phase. This begins with expert opinion. Remember, this in not designed for individual effort, but rather as a team activity. Therefore, the validity of Measure stands entirely on the opinion of the experts on the team.
Tools for collecting the X / Y relationships, based on expert opinion, comprise the entire Measure Phase. In other words, there are no statistics or active manipulation of variables at this point. There is plenty of time for that stuff later.
The Measure Phase uses traditional brainstorming and prioritization tools. It generally starts with some type of process map. The idea behind mapping is to begin to reveal the X / Y relationships. In other words, the map collects the relationships between the processes in-puts to the process out-put for each step in the process being considered. This will identify the X's (in-puts) that may promote to Red X's as the Measure Phase unfolds.
Many X's will be identified and an exhaustive examination will be required to prioritize them. This is accomplished through a system of forced ranking. The Measure System will continue to apply traditional tools for ranking. These can include things like Cause & Effects Matrixes, FMEA, and other methods to create ranking numbers. The large numbers, during ranking, will begin to identify the Red X's.
Think of this as going down through a funnel. At the top is a collection of many X's. Then as you progress down through the funnel, through the use of ranking tools, X's begin to be discarded. This process is exhaustive and will deliver the Red X's as you approach the bottom of the funnel.
The idea is to collect every important X / Y relationship possible and then, through the use of expert opinion, reduce them to identify the most important ones. The X's that survive are on their way to the next phase, "Analyze". During the Analyze Phase the opinion of the experts is subjected to statistical methods to validate the expert opinion. In the next installment of this series, we will link Analyze to Measure.