Tag: Variation

Span is a descriptor of the spread or variation of your data. It is a simple calculation that eliminates the impact of any outliers or unusually high or low values in your data set.

This article will introduce you to common cause variation, one of the foundational concepts in quality improvement. We’ll explore guidance for the successful use of common cause variation in process improvement.

As the Chinese proverb says, “a picture is worth a thousand words.” The multi-vari chart is such a picture. In a single graph, you will be able to understand the variation of your process. Let’s learn more. 

When it comes to variance, there are two main types to consider. These are common cause and special cause. Common cause variations usually do not pose much of a problem. Special case variations are another story.

Is random variation a good thing or a bad thing? Should I worry about the statistical implications or the practical ones? Let’s find out.

This article will introduce you to special cause control chart patterns. You will learn why special cause variation is one of the foundational concepts in quality improvement and the use of special cause variation in process improvement.

Common cause vs. special cause variation, aren’t they the same thing? At first glance, you’d be allowed to think so. However, as with any part of the production cycle, there is a reason for these two measurements to exist. So, let’s dive right into what makes these variations different, and how to identify […]

Who knows more about what it takes to improve digging ditches – the person holding the shovel or the executive vice president of ditch digging? Learn from a self-described Gemba nerd as he takes us behind the scenes in a Lean powerhouse.

A box plot may seem like a simple tool, but as this example shows it can help reveal common and special cause variation that may not have otherwise been noticed. Be sure you’re looking below the surface to optimize your performance!