Fonseca
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Fonseca replied to the topic Shainin vs. 6sigma in the forum General 12 years, 7 months ago
Hello Bob –
I’m in the middle with a discussion with our Customer in regards to GR&R studies via ANOVA and ISOPLOT. I’ve been through a Shainin training several years ago and I don’t remember how to plot and or calculate the DR. Would you have some document to send me so I can review over the weekend in preparation for tomorrow’s discussion?…[Read more] 
Fonseca replied to the topic FMEA scales in the forum General 13 years, 2 months ago
Have you ever used some Benefit versus Efford matrix?
In general you will find this under topics related with QFD or Quality House. 
Fonseca replied to the topic Yield calculation for out of control processes in the forum General 13 years, 7 months ago
Thank you, QualityColorado.

Fonseca replied to the topic Sampling for continuous process in the forum General 13 years, 7 months ago
Thank you, Chad.

Fonseca replied to the topic Sampling for continuous process in the forum General 13 years, 7 months ago
Thank you, but the tradtional articles and textbooks are limited to discrete sampling. In fact, I need to sample a continuous flow, like the flow of water or oil inside a pipeline. There is no room for rational subgrouping or sampling units. Maybe there is a simple solution for it, but I can´t see.

Fonseca replied to the topic Estimating accumulate yield in the forum General 13 years, 8 months ago
For the second step of the process the defectives and the defects are the same thing. The transmission of the sales order by an electronic means can be deemed defective or nondefective, but as the opportunity is equal one for each transmission, I am not taking into consideration the defects anymore. As I said, the opportunities are different in…[Read more]

Fonseca replied to the topic Estimating accumulate yield in the forum General 13 years, 8 months ago
Thank you,
Is there any problem in the fact that I am counting defects in the first step and counting defectives in the second ? In other words, the opportunities are from different natures.
Marcelo

Fonseca replied to the topic Problems with Six Sigma Metrics in the forum General 13 years, 9 months ago
What is “No”?

Fonseca replied to the topic Problems with Six Sigma Metrics in the forum General 13 years, 9 months ago
Thank you, QualityColorado.
In fact I know that probability distributions don´t exist. They are just models to approximate the reality. I am worried about all this metrics stuff because the socalled “sigma level” relies on a standard normal table and the 1.5sigma shift. Of course, that is the case where you want to state your process quality in…[Read more] 
Fonseca replied to the topic ANOVA for count data in the forum General 13 years, 10 months ago
Thank you, “Contingency”.
I will use one of my factors as a random factor.

Fonseca replied to the topic ANOVA for count data in the forum General 13 years, 10 months ago
Thank you. It is a completely new procedure to me. I am not sure if I can find a statistical package that is able to help me with it. But I will try for sure.

Fonseca replied to the topic ANOVA for count data in the forum General 13 years, 10 months ago
Thanks.
In fact, I need to study possible interactions, what I cannot do if I use ChiSq. I have more than 2 levels for each one of the 2 factors. 
Fonseca replied to the topic A real case study in the forum General 16 years, 8 months ago
Thank you for the tips, Darth.
However, the majority of the examples come from services and transactional areas. It would be very good to find something related to the automotive industry, for example.
Marcelo

Fonseca replied to the topic How to calculate Zst Zlt??? in the forum General 16 years, 9 months ago
Thank you very much Chris, C Seider and mjones !!!
There are really some differences among the calculations. I think that it is advisable to consider the closest specification limit.
Just the other day I was told by a friend (Phd in Statistics and a very respected researcher) that one of the main failures of Six Sigma is to estimate the…[Read more] 
Fonseca replied to the topic How to calculate Zst Zlt??? in the forum General 16 years, 9 months ago
Chris,
I am very grateful to you but I think I am not explaining correctly what is my doubt. I know everything you wrote in your message. The problem is that some years ago I was told that I could obtain Zst and Zlt through out these expressions:
Zst = 3*Cp and Zlt = 3*Ppk
Is it right or wrong ? The mathematical expression for Ppk has a number…[Read more] 
Fonseca replied to the topic How to calculate Zst Zlt??? in the forum General 16 years, 9 months ago
Thank you C Seider, but my doubt still remains.
Cpk is defined as the minimum of CPU and CPL. Therefore if I say that Zst = 3*Cpk, it means that calculation of Zst cannot use the CPU and CPL combined.
Where is my mistake ? 
Fonseca replied to the topic How to calculate Zst Zlt??? in the forum General 16 years, 9 months ago
Dear Hongkeat,
I saw your answer with a 2 months delay and I wonder if you could explain to me why Zst = 3Cpk. I thought that Zst = 3Cp.
Thank you,
Marcelo 
Fonseca replied to the topic Six Sigma Training for Top Management in the forum General 17 years, 5 months ago
Ron,No problem with your way of thinking….My opinion is just the same but you know that sometimes we need to fit to the company we are working for. Two hours and a half is the maximum that I can catch the managers attention…. And many times they have to live the class….I will never degrade the material but sometimes we have to make litlle…[Read more]

Fonseca replied to the topic Six Sigma Training for Top Management in the forum General 17 years, 5 months ago
Thanks for the answers !I think I haven´t explained the problem correctly. I had previously organized a course that took ~ 60 hours and was extensively based on quantitative tools. The problem with this next class is that it will be a “mixed” class, with managers, financial analysts and the CEO. He liked the idea and decided to encourage the i…[Read more]

Fonseca replied to the topic Stepwise Regression in the forum General 18 years, 4 months ago
James,
Would you mind to send me your email in order I can show you the data I am dealing with ?
Thank you very much,
Marcelo  Load More