Tips and Techniques for Statistics and Quality Improvement

Blog posts and articles about using Minitab software in quality improvement projects, research, and more.

Marilyn Wheatley

Marilyn Wheatley is a technical support specialist at Minitab Inc.

With Minitab, it’s easy to create graphs and manage numeric, date/time and text data. But Minitab’s enhanced data manipulation features make it easier to work with text data, too.

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Users often contact Minitab technical support to ask how the software calculates the control limits on control charts.

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As a person who loves baking (and eating) cakes, I find it bothersome to go through all the effort of baking a cake when the end result is too dry for my taste. For that reason, I decided to use a designed experiment in Minitab to help me reduce the moisture loss in baked chocolate cakes, and find the optimal settings of my input factors to produce a moist baked chocolate cake. I’ll share the details of the design and...

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While there are many graph options available in Minitab’s Graph menu, there is no direct option to generate a waterfall chart. This type of graph helps visualize the cumulative effect of sequentially introducing positive or negative values.

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In regression, "sums of squares" are used to represent variation. In this post, we’ll use some sample data to walk through these calculations.

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While some posts in our Minitab blog focus on understanding t-tests and t-distributions this post will focus more simply on how to hand-calculate the t-value for a one-sample t-test (and how to replicate the p-value that Minitab gives us). 

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Here is a scenario involving process capability that we’ve seen from time to time in Minitab's technical support department. I’m sharing the details in this post so that you’ll know where to look if you encounter a similar situation.

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While many Six Sigma practitioners and other quality improvement professionals like to use the Fishbone diagram in Companion for brainstorming because of its ease of use and integration with other Companion by Minitab tools, some Minitab users find an infrequent need for a Fishbone diagram. For the more casual user of the Fishbone diagram, Minitab has the right tool to get the job done.

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We often receive questions about moving ranges because they're used in various tools in our statistical software, including control charts and capability analysis when data is not collected in subgroups. In this post, I'll explain what a moving range is, and how a moving range and average moving range are calculated.

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Since opening a new office in Phoenix to support our customers on the West Coast, some evenings in Minitab technical support feel busier than others. (By evenings, I mean after 5:30 p.m. Eastern time, when the members of our tech support team in Pennsylvania go home for the day, and I become an office of one.)

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