Improvement Insights Blog

Posts tagged "Bar Chart"

Trends Are Not Always Improvements

Line charts with trend lines can be misleading. They can provide a kind of “false positive” that implies improvement where there is none. Here’s why:

“Hi, I’m Jay Arthur, author of “Agile Process Innovation.”

“I go to all these trade shows and I see a lot of poster presentations but they’re using line charts and then they draw a trend line through them and then they say, “Oh, we made an improvement.” No you didn’t. If it doesn’t really fit the line very well, if your goodness-of-fit metric is less than 80%, I’m not buying it. But nobody gives me a goodness-of-fit metric called r-squared, they just show me a line graph or a bar chart and then they show a little line through it.

Continue Reading "Trends Are Not Always Improvements"

Posted by Jay Arthur in Improvement Insights.

Why Are People Using Line and Bar Charts, not Control Charts?

If you look at improvement project posters at quality conferences around the country, you’ll find that almost everyone is using Excel line and bar charts. Even after decades of Six Sigma training and association membership. What’s the hold up? Here’s my take:

“Hi, I’m Jay Arthur, author of “Lean Six Sigma Demystified” and QI Macros [software].

“Every year I look at lots of improvement posters and I keep wondering, “Why isn’t anyone using the tools of Quality?” Control charts, Pareto charts, histograms… Most of them are just using plain old Excel line and bar charts. Now it might be because they don’t know about the power and beauty and how easy it can be now to do Control charts, Pareto charts and fishbones.

Continue Reading "Why Are People Using Line and Bar Charts, not Control Charts?"

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