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Glossary Index

2
3
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z

Z Distribution (Standard Normal). The Z distribution (or standard normal distribution) function is determined by the following formula:

f(x) = 1/[(2p)1/2] * e**{-1/2*x2}

-8 < x < 8

where

e is the base of the natural logarithm, sometimes called Euler's e (2.71...)
pi is the constant Pi (3.14...)

Note that this distribution is simply a normal distribution where the mean is zero and the standard deviation is one. The Z distribution is commonly used in hypothesis testing for large samples or in situations where the standard deviation is known.