WOLFRAM|DEMONSTRATIONS PROJECT

Comparing and Weighting Two Weibull Models

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Weibull parameters
model one
α
1
β
1
model two
α
2
β
2
plot options
function
PDF
CDF
style
mono
color
weights 1
model
α
β
weight 1
weight 2
one
1
200
19.200
200.000
two
2
200
17.720
177.200
The Weibull model is widely used for estimating the reliability of engineering materials. More reliable parts tend to last longer (i.e. have a large time before failure). Estimates of Weibull model parameters can be achieved by using a least squares method to fit a straight line on a logarithmic plot. This Demonstration describes a method for comparing two Weibull models for reliability via weight measures. The PDFs or CDFs are plotted.
The weight functions measure a combination of failure time and failure probability. For a chosen weight function, larger weight values indicate higher reliability of the material whose failure time follows that Weibull distribution.