Typical sigma score

To my knowledge there are no published results of empirical studies performed by a knowledgable & objective ‘auditor’ or ‘researcher’ of sigma levels of any company let alone a large enough sample to prove an estimate of what ‘most’ companies operate at.  (And I would suppose that a peer reviewed study would be too much to ask?)
If there are any, I’d love to see the studies.  They would be quite valuable in determining what to do to achieve success. 
I have heard and read numerous anecdotal accounts of where a particular company thinks (is ‘telling’ people) they are running. 
I have heard and read numerous educated – and some not so educated – guesses at where certain categories of companie are ‘most likely’ running.  But most of these are based on a subjective analysis of warranty rates and guesses at internal failure rates…not very reliable sources.  
 
So if anyone knows of such studies in the public domain please let us know.

Most average Companies are operating ca.3 Sigma level.Successful exporting companies can exceed this level and operate at 3,5-4,5 Sigma level.Some few International Companies (such as Motorola,GE,IBM,TOYOTA…etc) operate above 4,5 and sometimes exceed 5 Sigma.My opinion based on my experience and readings. MN

My experience with 6 – sigma is only within a transactional environment, although I’m often in contact with manufacturing Black Belts; I would suggest that for large transactional processes with numerous opportunities for errors and time delays (which will be 2 separate sigma measures) that 3 sigma is a goal, 4 is exceptional & 4+ is the “promised land”.

I think those who post a sigma value, could be more helpful to say how they measured it? what formula? did they include shift factor?

Survival industries typically maintain 3 sigma (short term). But , please note there is truly no typical value of sigma level. It’s entirely dependent on the process / product. At Six sigma level (short term) 3.4  defects are allowed in 1 million of opportunities for making defect . Just imagine , can we afford to having aeroplane engines or medical equipements at Six Sigma level ? If yes , then we are virtually accepting 3.4 aeroplane crashes in 1 million of flying opportunities.
Six Sigma organisations find out the critical processes & according to criticality , sigma level to be maintained for the process / product  is determind. It’s also important to note that simply focussing on sigma level improvement is no way recommended because cost of quality will unncessarily increase.
Thanks!
 

So, if your company is, say . . . at 3 sigma, you still make a lot of junk, but you’re at least better than average!
For some reason , this reminds me of a quote I once heard from some news type, that went something like this:  “Even after all the money spent on improving education, 50% of the students are still below average!”  Knowing the typical sigma score of companies as an aggregate has about as much meaning to me as this quote, I guess.
Shooter

I agree with Stan. This would be an impossible figure to estimate accurately in a single company, yet alone across all companies.I have had cases where managers hit what they labeled as “six-sigma” perfection in a single process and wanted therefore to back-off on process improvement. After doing a brief exercise where they estimated (roughly) the sigma level of their top 5 supporting processes, the grand sigma average dropped precipitously. When this was expanded to 10 processes, and more, the grand value kept dropping, and in some cases it dropped embarrassingly low. I am yet to find an organization that did not have a lot of room for improvement when the totality is looked at. Anyone can make one process sparkle at the expense of other processes.

Geez – it’s too early – or maybe just too short a timeframe after yesterday’s festivities?.  The aforementioned chart does not show that reducing complexity will increase yield and sigma level.  It shows how it improves yield for a given sigma level.  Sorry ’bout that, ya’all.
Shooter
 

Exactly – they are all part of a system.  That’s why systems thinking is so important.  The one that gets me is when someone touts how they have “optimized” a process, only to find out that they have suboptimized the system and other processes in the value stream.  Usually, by the time the suboptimization has been discovered, the “hero” has been promoted and has left the newbie holding the bag for the consequences.  “What a world! What a world . . .!”
Shooter