Statistics
An engineer once told me, “I work on project teams that have an average half-life of two weeks, implementing solutions with an average half-life of two weeks.” Time after time, and in place after place, our improvement efforts often fall short of expectations and fade away. In this article, I…
The 2024 U.S. presidential election is shaping up to be one of the closest in recent history, with Kamala Harris and Donald Trump locked in a dead heat in many polls. This razor-thin margin amplifies the effect of even small demographic changes, such as those driven by the recent surge in remote…
Most quality practitioners are familiar with the Taguchi loss function, which contends that the cost of any deviation from the nominal follows a quadratic model. This is in contrast to the traditional goalpost model, where anything inside the specification limits is good, and anything outside…
The objective of all improvement projects should be to improve the overall process. Everything else should be secondary to this objective. If you improve the efficiency of a support process, or even a portion of the core process, but at the same time lower the efficiency of the overall process,…
Recently, I wrote about the process capability index and tolerance interval. Here, I’m writing about the relationship between the process capability index and sigma. The sigma number here relates to how many standard deviations the process window can hold.
A +/– 3 sigma contains…
The four common capability and performance indexes collectively contain all of the summary information about process predictability, process conformity, and process aim that can be expressed numerically. As a result, any additional capability measures that your software may provide can only…
