The Lights Are On, But Nobody Is HomeTraffic light monitoring systems require modifications to be effective
Wed, 02/06/2013 - 10:24
There are many different process control methods and procedures available to the quality practitioner. A popular but problematic visual technique employs the traffic light analogy.
As discussed in the article, “Stoplight Charts With SPC Inside,”… Process Capability ConfusionProper understanding of rational subgrouping is fundamental to statistical process control
Tue, 01/15/2013 - 09:35
You may have noticed that there is a huge amount of confusion with regards to the process capability indices Cp’s and Pp’s (see the iSixSigma website). Specifically, the confusion centers around when to use which one and what they mean. I would say… Making and Interpreting Run ChartsUse this helpful tool to assess process stability and discover patterns
Thu, 08/11/2011 - 14:14
A run chart is a graphical display of data over time. Run charts are used to visually analyze processes according to time or sequential order. They are useful in assessing process stability, discovering patterns in data, and facilitating process… The Sound of One Tail Flapping Normality, tail probabilities, and SPC
Wed, 07/06/2011 - 16:07
Story update 7/08/2011: We corrected an error in Figure 2, and in the section preceded by "Expressed symbolically for a stable process...".
Two topics that have generated significant interest and frequent comments are, “Is normality required for… Myth or MythunderstandingImplications of the economic design of control charts
Thu, 05/12/2011 - 06:00
In the article, “Four Control Chart Myths from Foolish Experts,” by Davis Balestracci (Quality Digest Daily, March 30, 2011) the following comments were made regarding what Balestracci considers statistical process control (SPC) myths:
“Myth No. 4:…
