‘What’s the Trend?’Wrong question!
Mon, 08/11/2014 - 11:13
In my last column, I showed how hidden special causes can sometimes create the appearance of common cause, but the purpose of common-cause strategies is to deal with this and smoke them out. When there's an underlying structure to how these data… More Common Cause SubtletyYou’ve got a chart, and it’s common cause. Now what?
Mon, 07/28/2014 - 11:46
I was teaching a class and asked participants to create a control chart of an indicator that was important to them. A lab supervisor presented me with a chart on the number of procedures her department performed and told me that it wasn’t very… Count Data: Easy as 1-2-3?Hardly!
Mon, 07/07/2014 - 12:18
Author's note: To my non-U.S. readers, I apologize for using the sport of baseball to make my points today—and during the World Cup, no less! It’s a perfect context, however, and I hope you will be able to understand the main points.
In my last… Right Chart or Right Action?No extra credit for choosing the technically correct chart
Wed, 06/11/2014 - 14:52
Do you still insist on asking, “Which chart do I use for which situation?”
I’ve seen many flowcharts in books to help you answer this question. They’re all some variation of this:
I find them far too confusing for the average user and have never… Are Your Processes ‘Too Variable’ to Apply Statistical Thinking? I doubt it
Wed, 05/28/2014 - 10:52
My recent columns have emphasized the need for critical thinking to understand the process that produces any data. By just plotting data in their naturally occurring time order, many important questions arise about the data’s “pedigree” (a term… Yet Another Predictable Question How many data points do I need to have a good chart?
Mon, 05/12/2014 - 08:50
In my last column, I considered two of the most common questions faced by a statistical educator and the deeper questions that need to be addressed. I encouraged people to consider their everyday reality for the necessary context. Predictably, some… Two Questions That Get You Nowhere‘The purpose is not to have charts. The purpose is to use the charts.’
Tue, 04/29/2014 - 16:34
In my column, “The Universal Process Flowchart × Four,” I challenged you to look at the everyday use of data as a huge source of hidden waste. I suggested looking at a sample of any routine meeting’s raw data and asking eight questions, the last of… PDSA… or Rock of Sisyphus?PDSA is a messy, ugly, nonlinear process... that you absolutely need
Wed, 04/16/2014 - 17:43
Critical thinking does not necessarily result from using a practitioner’s toolbox framed within a formal improvement structure such as Six Sigma, lean, lean Six Sigma, or the Toyota Production System. It’s very easy to get seduced by all the fancy… The Universal Process Flowchart × 4This tends to get a whole lot of emotional interpretation flowing
Mon, 04/07/2014 - 15:52
To summarize my last three articles, most improvement approaches come out of the same theory and are based on the assumption that everything is a process.
The universal process flowchart in Figure 1 sums it up beautifully. The boxes at the top are… Finding the Unnecessary and Everyday VariationThe last two sources of problems
Wed, 03/19/2014 - 12:14
This is the last in my series making the case that the various improvement approaches are all pretty much the same.
There are seven sources of problems with a process. The first three help frame the situation: Source 1: Inadequate knowledge of…
