Users Guide Instruction Manual

A • STATISTICAL DISTRIBUTIONS
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A • Statistical Distributions
Normal( μ , σ )NORMAL(Mean, StdDev) or NORM(Mean, StdDev)
The mean ( μ ) specified as a real number and standard deviation ( σ ) specified as a positive
real number.
(−∞, +∞)
μ
σ
2
The normal distribution is used in situations in which the central limit theorem applies;
i.e., quantities that are sums of other quantities. It is also used empirically for many
processes that appear to have a symmetric distribution. Because the theoretical range is
from - ∞ to + ∞, the distribution should only be used for positive quantities like
processing times.
Probability
Density
Function
)2/()(
22
2
1
)(
σμ
πσ
−−
=
x
exf
for all real x
P
arame
t
ers
Range
Mean
Variance
Applications