Dakota Reference Manual  Version 6.4 Large-Scale Engineering Optimization and Uncertainty Analysis
weibull_uncertain

Aleatory uncertain variable - Weibull

## Topics

This keyword is related to the topics:

## Specification

Alias: none

Argument(s): INTEGER

Default: no weibull uncertain variables

Required/Optional Description of Group Dakota Keyword Dakota Keyword Description
Required alphas First parameter of the Weibull distribution
Required betas Second parameter of the Weibull distribution
Optional initial_point

Initial values

Optional descriptors

Labels for the variables

## Description

The Weibull distribution is also referred to as the Type III Smallest Extreme Value distribution. The Weibull distribution is commonly used in reliability studies to predict the lifetime of a device. It is also used to model capacity variables such as material strength.

The density function for the Weibull distribution is given by:

where and