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uniform_uncertain


Aleatory uncertain variable - uniform

Topics

This keyword is related to the topics:

Specification

Alias: none

Argument(s): INTEGER

Default: no uniform uncertain variables

Child Keywords:

Required/Optional Description of Group Dakota Keyword Dakota Keyword Description
Required lower_bounds Specify minimum values
Required upper_bounds Specify maximium values
Optional initial_point

Initial values for variables

Optional descriptors

Labels for the variables

Description

The number of uniform uncertain variables and their distribution lower and upper bounds are required specifications, while variable descriptors is an optional specification. The uniform distribution has the density function:

\[f(x) = \frac{1}{U-L}\]

where $U$ and $L$ are the upper and lower bounds of the uniform distribution, respectively. The mean of the uniform distribution is $\frac{U+L}{2}$ and the variance is $\frac{(U-L)^2}{12}$.

Theory

This distribution is a special case of the more general beta distribution.

For some methods, including vector and centered parameter studies, an initial point is needed for the uncertain variables. When not given explicitly, these variables are initialized to their means.