2007-07-18 00:05:23 · 3 answers · asked by goutam a 1 in Science & Mathematics ➔ Engineering
Six sigma is a method for quality management which is intended to free products and services from errors. business processes are described in a way that represents the customer's view. Results are analyzed and measured.
2007-07-18 00:11:08 · answer #1 · answered by Anonymous · 0⤊ 0⤋
It is six sigma, not zigma. It refers to minimising the variation in any process so that the process quality is maintained in more narrow limits.
Sigma is the standard deviation and a conventional manufacturing process has 2 or 3 sigma levels, that means that the tolerance given for a parameter spans - 3 sigma to + 3 sigma of a normal distribution curve (also called bell shaped distribution or a Gaussian distribution). So, a few parts per thousand will go out of tolerance and may need rework or lead to rejection.
In six sigma, the same tolerance is distributed across a normal distribution curve from - 6 sigma to + 6 sigma. Thus the distribution is narrower compared to a 3 sigma curve. Even a slight shift in process doesn't lead to heavy rejection and the defect rate is only a few ppb.
2007-07-18 07:21:39 · answer #2 · answered by Swamy 7 · 1⤊ 0⤋
In addition to Swissgirl's great answer, do some research on Edward Demming. He was instrumental in bringing this concept to American businesses.
2007-07-18 07:14:33 · answer #3 · answered by Anonymous · 0⤊ 0⤋