control chart

Posts tagged "control chart"

Run Charts vs Control Charts

Run charts used to be a bridge to control charts. You no longer need to build a bridge. Just start with Control Charts.

Posted by Jay Arthur in Improvement Insights, Jay Arthur Blog, QI Macros, Six Sigma.

Quality Improvement Movement

The editor of Harvard Business Review says that “corporate survival today requires the capacity for rapid change.” Isn’t it time to embrace an Agile approach to Lean Six Sigma to “speed its evolution and better serve customers’ needs?”


Join the Agile Quality Improvement Movement!

Posted by Jay Arthur in Improvement Insights, Jay Arthur Blog, Lean, Six Sigma.

Nobody Wants to Read Your Spreadsheet!

Nobody wants to read your spreadsheet! No matter how hard you try to make it pretty, create great labels or whatever, the only person who can read your spreadsheet is a CFO or Excel spreadsheet geek. And the Excel geek is going to tell you 10 ways to make it prettier.

The purpose of data is to provide insights for action, not just report past performance.

How Do I Know That Most Excel Users Try to Make Their Spreadsheets Readable By People?
According to Renu Davi, Sr. Program Manager for Excel, Microsoft tracks how people use Excel. The vast majority of the 650 million users use it for lists and reports.

Posted by Jay Arthur in Data Mining, QI Macros, Six Sigma.

How to Craft an Improvement Story

In 1975, I went to work at Bell Laboratories in New Jersey. I was introduced to Unix and the Shell programming language. The cool thing about Shell was the hundreds of tools that each did simple things and could be cobbled together into scripts that would do amazingly complex things. I later wrote a book, Unix Shell Programming, that described my love affair with Shell.

Fast forward 20 years and I brought the same thinking that I’d learned from Unix Shell to Six Sigma. The QI Macros have hundreds of templates filled with a variety of worksheets to do many things.

Posted by Jay Arthur in QI Macros, Six Sigma.

Data Visualizations that Really Work

The June, 2016 HRB article by Scott Berinato examines how to use charts and diagrams to express ideas and statistics. I agree with Anmol Garg, Tesla data scientist quoted in the article, “You can’t find anything looking at spreadsheets and querying databases. It has to be visual.”

Bernato says: “Convenient is a tempting replacement for good, but it will lead to charts that are merely adequate or, worse, ineffective.” He separates visualizations into four components: idea generation, idea illustration, visual discovery and everyday dataviz. Simple line, bar and pie charts are great for idea generation and illustration, but terrible for visual discovery and dataviz.

Posted by Jay Arthur in QI Macros, Six Sigma, Statistics.

First Stability then Capability Analysis

I recently got a question from a QI Macros user. His Cp/Cpk was high, while his Pp/Ppk were low. He wondered if there was a problem with the calculation in the QI Macros.


Whenever Cp is more than a third higher than Pp, it means the process isn’t stable. And a process has to be stable before you can do capability analysis. How do you check stability? With a Control Chart. Here’s the data in an XmR chart:


As you can see, the process runs at three different levels. I have found that any process shift, not matter how small will create out of control conditions that prohibit capability analysis.

Posted by Jay Arthur in QI Macros, Six Sigma.

Binomial, Poisson, Attribute, Continuous Data Control Chart Confusion

A customer called today confused about her data. She wanted to draw a control chart and thought the data might have a binomial or poisson distribution. She thought it was attribute data. She’d used the QI Macros Control Chart Wizard to create a control chart of her data and it chose an XmR chart. She wasn’t sure that was right. When I asked her what kind of data she had, she said, “write-offs”.

Write-offs are money, plain and simple. Money is variable (a.k.a. continuous or measured) data.

I explained that to her and suggested she stop worrying about what kind of distribution she has and just look at her data.

Posted by Jay Arthur in QI Macros, Six Sigma.

IHI 2015 Poster Use of Quality Tools

In his speech Sunday at IHI, Don Berwick called for everyone to “recommit to improvement science” (step 5 in ERA 3 of healthcare transformation).

He sounded annoyed with the lack of use of Lean Six Sigma tools and methodologies.

I understand his frustration. I was there in 2006 when he asked everyone to “pledge allegiance to science and evidence.”

Over the years, I’ve done a stroke tally of the quality tools used in IHI poster presentations.

I gave each poster one checkmark for each type of tool used.


Sadly, even with all of the emphasis on control charts, Pareto charts and other tools of quality, they are used rarely in poster presentations.

Posted by Jay Arthur in healthcare, QI Macros, Six Sigma.

Use Control Charts to Determine Process Stability

Control Charts show your data as a line graph with average and sigma lines to determine stability.  The average and sigma lines are calculated from your data. It’s easy to create a control chart in excel using the QI Macros.  See

Posted by Jay Arthur in QI Macros.