Rockwell Automation Arena Basic Edition Users Guide - Manual (Page 65)

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Statis
tical
Dis
tribu
tions
Statistical Distributions
Arena contains a set of built-in functions for generating random numbers from the com-
monly used probability distributions. These distributions appear on pull-down menus in
many Arena modules where they’re likely to be used. They also match the distributions in
the Arena Input Analyzer. This appendix describes all of the Arena distributions.
Each of the distributions in Arena has one or more parameter values associated with it.
You must specify these parameter values to define the distribution fully. The number,
meaning, and order of the parameter values depend on the distribution. A summary of the
distributions (in alphabetical order) and parameter values is given in the table below.
Summary of Arena’s Probability Distributions
Distribution Parameter Values
Beta BETA Beta, Alpha
Continuous CONT CumP
1
,Val
1
, . . . CumP
n
,Val
n
Discrete DISC CumP
1
,Val
1
, . . . CumP
n
,Val
n
Erlang ERLA ExpoMean, k
Exponential EXPO Mean
Gamma GAMM Beta, Alpha
Johnson JOHN Gamma, Delta, Lambda, Xi
Lognormal LOGN LogMean, LogStd
Normal NORM Mean, StdDev
Poisson POIS Mean
Triangular TRIA Min, Mode, Max
Uniform UNIF Min, Max
Weibull WEIB Beta, Alpha