Process Behavior Charts and Chaos Theory
"Chaos Theory" Credit: Boon Chin Ng
Walter Shewhart made a distinction between common causes and assignable causes based on the effects they have upon the process outcomes.
"Chaos Theory" Credit: Boon Chin Ng
Walter Shewhart made a distinction between common causes and assignable causes based on the effects they have upon the process outcomes.
Quality-related data collection is useful, but statistics can also deliver misleading and even dysfunctional results when incomplete.
Many different approaches to process improvement are on offer today. An appreciation of the way each approach works is crucial to selecting an approach that will be effective.
Students are told that they need to check their data for normality before doing virtually any data analysis. And today’s software encourages this by automatically providing normal probability plots and lack-of-fit statistics as part of the output.
Acceptance sampling uses the observed properties of a sample drawn from a lot or batch to make a decision about whether to accept or reject that lot or batch.
As municipalities clamor for a slice of President Biden’s $1.2 trillion infrastructure spending bill, one Johns Hopkins scientist is re-examining one of the basic elements of road-building: Determining the width of road lanes.
"in context" Credit: Erin Brown-John
In 2010, new to the world of statistical process control (SPC), I was intrigued by Don Wheeler’s statement that “No data have meaning apart from their context” (from his book, Und
All too often the topic of fixing dirty data is neglected in the plethora of online media covering artificial intelligence (AI), data science, and analytics. This is wrong for many reasons.
Last month we looked at analyzing observational data. Here we will consider experimental data and discover a weakness in the way they are obtained that can contribute to
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