General Statistics
Symbol Description Table ( E - L)
Index: A - D
 E - L 
 M - O
 P - Q 
 R 
 S 
T -W 
X -Z 
Symbol Description Symbol Description
E1, E2, .. Events in a decision structure ENGS Expected net gain of sampling
EVPI Expected value of perfect information EVSI Expected value of sample information
e (1) Tolerable error level; used in establishing required sample size

(2) Base of natural logarithms

 - epsilon Error term in regression analysis
Error term in two-factor analysis of variance Error in forecasting using exponential smoothing
F F statistics; used in analysis of variance Critical value for the F-statistics (random variable); represents the value exceeded 1-  proportion of times by F.

(see F- table)
Ft Forecast value for period t; used in exponential smoothing f Frequency of observations falling into a particular class interval
f(x) Function f used to represent the height of the density curve (taht is, f(x) is the probability density function of the random variable X) f1, f2, f3,.. Class frequencies for successive class intervals of a frequency distribution; used in calculating sample mean or standard deviation with grouped data
fa, fe, Actual and expected class frequencies used in calculating the test statistics  - gamma Smoothing parameter for trend in two-parameter exponential smoothing
H0 Null hypothesis Ha Alternate hypothesis
I Value of an index number It Irregular component of classical time series model
i (1) Subscripts in a summation (  )

(2) Index to elements in a series

 j Used to represents subscripts in a double summation:

Lj Lower limit of class interval Logarithm to base 10 of ; used in simple regression to find exponential trend curve, 

lambda

 Mean rate at which events occur in a Poisson process Mean arrival and service rates used in queuing applications