Literature Review: History of Six sigma

Motorola®	Allied Signal®	General Electric®	Philips®	Sony, Toshiba…
1987	1994	1996	1996	2000
(Strength In Mfg)	(Linked to Financial Results)	(Linked to Design & Service)	(Linked to Sales & Product commercialisation)

Since 2001, large number of Organisations globally have taken up the initiave and got benefit out of it.

Six Sigma:

Six Sigma is a disciplined, data driven approach and methodology for eliminating defects (driving towards six standard deviations between the mean and the nearest specification limit) in any process -- from manufacturing to transactional and from product to service.

The statistical representation of Six Sigma describes quantitatively how a process is performing. To achieve Six Sigma, a process must not produce more than 3.4 defects per million opportunities. A Six Sigma defect is defined as anything outside of customer specifications. Six Sigma is a statistical unit of measure which reflects process capability. The sigma scale measure is perfectly correlated to such characteristics as defects per unit, parts per million defective and the probability of a failure/error.

The lower case Greek letter, s, is pronounced sigma. In Six Sigma science, s is the symbol for a statistical measure called the standard deviation. This measure helps describe the shape of a bell curve like the one on this book’s cover. When one knows the average ( X ) and standard deviation (s) of a process, one can improve that process to near perfection.