Category: Tools & Techniques

Establishing the initial list of potential causes is often more art than science.  Unfortunately, the brainstorming process is still one of the best ways to surface candidate variables.  However, there are several other alternatives: 1)   Query process experts. 2)   Benchmark similar processes. 3)   Review the literature. 4)   Perform an Internet search. 5)   Conduct correlation study. […]

To facilitate an answer, we will consider three examples.  First, consider the game of baseball.  We understand the field-of-play consists of 9 positions.  The coach is “free” to assign any of the 9 players to any of the 9 positions. Once the 8th player is assigned to the 8th position, the 9th player-position is pre-determined, […]

Suppose we consider a specific bilateral critical-to-quality characteristic (CTQ).  In other words, we are in view of a key design feature that sports a two-sided performance specification.  If a bilateral design margin of “Y percent” was to be imposed on the given CTQ (during the course of product configuration), we indirectly and necessarily infer the […]

Let us suppose we are interested in testing the influence of a certain independent variable (say, A) as it relates to a given dependent variable (say, Y).  We will suppose the experimental factor (variable A) is to be tested at two competing settings (test levels).  In this scenario, the two levels will be called “high” […]

Arguably, acceptance sampling is an effective and efficient means to ensure the proper surveillance of product and service quality.  Using this approach, a random sample (of product or service) is inspected or tested to determine if the observed level of quality is acceptable or unacceptable.  If the sample supports the hypotheses of unacceptability, then certain […]

Please recognize that the “art and science” of process mapping is quite generic by nature.  You should apply the mapping tools, techniques, and procedures in the given situation just as you would in any other type of situation.  Granted, the variable labels will change – but that’s about it.  Simply stated, you must define what […]

Thanks to modern technology, we have before us a virtual mountain of information.  On the Internet, we can find many case studies on the subject of DOE (design-of-experiments).  For a wide area success stories and general discussion, you may want to visit the following websites: 1) http://www.statease.com/articles.html2) https://www.isixsigma.com/tt/doe/3) http://class.et.byu.edu/mfg340/lessons/designofexperiment/4) http://members.cox.net/asqsd/kn/publications.htm In addition to these sources, […]