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Q: Six Sigma ( Answered 5 out of 5 stars,   1 Comment )
Subject: Six Sigma
Category: Business and Money > Economics
Asked by: tomandsharonz-ga
List Price: $2.00
Posted: 02 Feb 2005 09:18 PST
Expires: 04 Mar 2005 09:18 PST
Question ID: 467582
How is six-sigma verified statistically?
Subject: Re: Six Sigma
Answered By: siliconsamurai-ga on 02 Feb 2005 10:01 PST
Rated:5 out of 5 stars
Hi, thank you for submitting your question to Answers.Google, I hope I
can provide the information you are seeking.

Six sigma, a mathematical term with a very specific meaning, has been
appropriated by the business community to indicate a high level of

Six sigma is also the designation for a high-IQ society similar to
Mensa but with much more stringent requirements. A six sigma club
today is more likely to be related to some high level of manufacturing

Six sigma?s mathematical meaning is that something measured comes
within + or ? six sigma (standard deviations) of a specified average.
In manufacturing this means about 3.4 defects in one million cases
whether this is customer responses, or manufactured items. Just what
constitutes a defect is always open to interpretation but once that is
established then determining six sigma qualification is simply a
matter of counting.

A standard deviation isn?t a specific number except in a specific
case. It is defined as the square root of the average of the squares
of the amount individual measurements differ from the mean (similar to
the average.)

You can learn about implementing 6-sigma quality procedures in a
business at

Google search string: six sigma

Google search string: define:standard deviation

So, a six sigma quality control program would result in 99.9997% perfect results.

Members of the six sigma IQ club have an IQ higher than 99.9997% of
the population (for Mensa it is only 98%.)

How do you verify or demonstrate this? Simple, count the number of
mistakes or defects and compare that to the total number of events or
products. If there are fewer than one bad outcome for every 300,000
then you have achieved six sigma quality.

Thank you again for turning to Answers.Google for help. I feel this is
a very complete answer for the price and hope you agree.
tomandsharonz-ga rated this answer:5 out of 5 stars
Exactly what I was looking for... Thank you! Tom Z.

Subject: Re: Six Sigma
From: 6sigma-ga on 21 Oct 2005 19:03 PDT
This answer is technically incorrect. Six sigma?s mathematical meaning
is that something measured comes within + or ? six sigma (standard
deviations) of a specified average.In manufacturing this means about
3.4 defects in one million cases.
If you calculate +/- 6 sd of a process, it produces far fewer defects
than 3.4.  Six sigma assumes processes will shift 1.5 standard
deviations in the long run.  Using that shift is how six sigma and 3.4
defects per million opportunities are associated.  You can learn more
about six sigma at or @

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