Origin and Meaning of The Term "six Sigma Process"
The term "six sigma process" comes from the notion that if one has six standard deviations between the process mean and the nearest specification limit, as shown in the graph, practically no items will fail to meet specifications. This is based on the calculation method employed in process capability studies.
Capability studies measure the number of standard deviations between the process mean and the nearest specification limit in sigma units. As process standard deviation goes up, or the mean of the process moves away from the center of the tolerance, fewer standard deviations will fit between the mean and the nearest specification limit, decreasing the sigma number and increasing the likelihood of items outside specification.
Read more about this topic: Six Sigma
Famous quotes containing the words origin, meaning, term and/or process:
“The origin of storms is not in clouds,
our lightning strikes when the earth rises,
spillways free authentic power:
dead John Brown’s body walking from a tunnel
to break the armored and concluded mind.”
—Muriel Rukeyser (1913–1980)
“A name with meaning could bring up a child,
Taking the child out of the parents’ hands.
Better a meaningless name, I should say,
As leaving more to nature and happy chance.
Name children some names and see what you do.”
—Robert Frost (1874–1963)
“Children, I grant, should be innocent; but when the epithet is applied to men, or women, it is but a civil term for weakness.”
—Mary Wollstonecraft (1759–1797)
“A man had better starve at once than lose his innocence in the process of getting his bread.”
—Henry David Thoreau (1817–1862)