Ward

Montana? Count me in. I have worked in 46/50 states and that is not one of them, and I can almost drive there!

I vote for Nancy Grace as a moderator. Just kidding!Actually, Terry Tate “Office Linebacker” might be more appropriate.

Stan, I agree, but I am astounded how many organizations have a difficult time identifying the process owner. Functional owners abound, but process owners is remain rare. Pete

The real learning is I don’t type so well, prior to having a cup of coffee. My typos were embarrassing. I am new to the discussion forum, but it already appears there are many contributors that would be great participants in a six sigma summit.

If you are using Minitab, remember to set “0” as a boundary, so it does not calculate the likelihood of performing less than “0”.

Stan,Thanks again for your response. I respect what you are saying regarding the instructor/class relationship. I do believe that ratio would work, but so many other factors have to be of high quality. There must be an appropriate sized class room, proper layout of the room, high quality training materials, and students should arrive with…[Read more]

Stan,Thanks for the response. I meant no disrespect to Montgomery. I reference his DOE book often. One of my first SPC texts was also Grant & Leavenworth. I whole-heartedly support Crosby’s idea that “Quality is Free”. If Six Sigma waves are not more than paying for themselves, something is wrong. Yes. You are spot with your regard to action…[Read more]

To be fair, I should add that just as I believe your comments can apply to organizations other than GEHC, not all my comments extend to all six sigma deployments.
As has been tossed around before, a standard would be helpful. I only know of a few people still around (Mike C.) who still aren’t afraid to walk out the door, if clients don’t want…[Read more]

Hunter,Again your comments are on the mark, but I don’t believe limited to GEHC. I left Six Sigma consulting because I lost faith in how it was being approached across the board. The model when I began consulting (1996, GE) was:
1) BB training was 4 weeks of classroom training over 4 months
2) When Lean Master training began it was 4 weeks…[Read more]

C,…Hamids original inquiry into the central limit theorem. My bias is evident, as I was trained by Dr. Wheeler (spcpress.com). I still go back to the practicality of the I-mR chart. When non-normal data is evident, then it is better to modify the rules for interpretation, than attempt elegant transformations to normality. Variables charts…[Read more]

C,I appreciate the tone of your response. I do think a new discussion thread should of been started regarding control charts. We seemed to have moved away from

Feel better?

A little cutting, but your points are valid. I reference Wheeler, who in turn references Deming and Shewhart.
“If you want to learn something new, read an old book.”

There is no assumption of normality for the control chart. There is no assumption of normality for the control chart. The 3 sigma limits work for the normal, uniform, right triangular, Burr, Chi-Square and exponential. Minitab cites Wheeler & Chambers when advising people of the Box-Cox transformation. “The Box-Cox transformation can be useful…[Read more]

I agree going to the customer is what you would like to do, but asking them is not always effective. Customers really don’t have a good sense of time. They may “say” 15 minutes is tolerable, but they just pulled that number out of a hat, so to speak. A better way might be to question them after service has been provided. You will have to…[Read more]

What is the purpose of transforming the data? If it is to determine process capability and you have at least five good and at least five bad, then just determine the percentage good and you have the yield.
If you must transform the data because you have less then five good and five bad, then whatever lambda value you use for the original data,…[Read more]

If you have Minitab 15,
Stat>Quality Tools>Individual Distribution Identification also works.

It seems this thread is now deviating (no pun intended) to control charts instead of the central limit theorem.
When addressing OC curves, alpha & beta risk, area under the curve & central limit theorem, it appears there is a fundamental misunderstanding between analytical studies (SPC) and enumerative studies (hypothesis testing).I think you…[Read more]

I agree with you but where is the reference to control charts?

If you have Minitab, Minitab also has a macro that demonstrates this:
” Demonstration of the Central Limit Theorem
Provides a “guided tour” of the Central Limit Theorem, simulating multiple throws of a die to demonstrate the theorem. Concepts are explained in notes in the Session window, and graphs show the results of simulations. The…[Read more]