Graphs a Gaussian distribution,
with given parameters mean, μ, and standard deviation, σ,
for a "lower specification limit", L, computing the "fraction defective",
i.e., below L. This fraction is essential in industry.
The base data refer, say, to a bag of coffee,
with nominal weight (mass) of 500 g, which is the legal
"lower specification limit", L. The producer attempts to obey this limit
by using a target weight of μ
(surely, μ > L),
the intrinsic variability of the weight being σ.
(For the base data, the fraction defective is 1.8 %.)
† Left and right in σ's
are ignored iff (not equal) weights are given.
A graph is drawn showing the Gaussian density
and its cumulative function, as well as the area corresponding
to the fraction defective (to the left of L).
Suggested other data: σ = 0.9 g
(with smaller σ leading to better quality, but typically difficult
or expensive to get, hence the need for
technico-economic optimization) or σ = 2 g
(possibly with weights both 0 g). |
• Ponce, V. M.,
"Vlab" (OnlineCalc),
San Diego State University, San Diego (CA), USA.
• 1889-11-20: Hubble, Edwin Powell (Expanding to ?...)
(1953-09-28). |