Template:Weibull reliability function: Difference between revisions

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=== The Weibull Reliability Function ===
=== The Weibull Reliability Function ===


The equation for the three-parameter Weibull cumulative density function, ''cdf'', is given by:  
The equation for the 3-parameter Weibull cumulative density function, ''cdf'', is given by:  


::<math> F(t)=1-e^{-\left( \frac{t-\gamma }{\eta }\right) ^{\beta }} </math>.
::<math> F(t)=1-e^{-\left( \frac{t-\gamma }{\eta }\right) ^{\beta }} </math>.


This is also referred to as ''Unreliability'' and designated as <math> Q(t) \,\!</math> by some authors.  
This is also referred to as ''unreliability'' and designated as <math> Q(t) \,\!</math> by some authors.  


Recalling that the reliability function of a distribution is simply one minus the cdf, the reliability function for the three-parameter Weibull distribution is then given by:  
Recalling that the reliability function of a distribution is simply one minus the ''cdf'', the reliability function for the 3-parameter Weibull distribution is then given by:  
::<math> R(t)=e^{-\left( { \frac{t-\gamma }{\eta }}\right) ^{\beta }} </math>
::<math> R(t)=e^{-\left( { \frac{t-\gamma }{\eta }}\right) ^{\beta }} </math>

Revision as of 22:51, 24 April 2012

The Weibull Reliability Function

The equation for the 3-parameter Weibull cumulative density function, cdf, is given by:

[math]\displaystyle{ F(t)=1-e^{-\left( \frac{t-\gamma }{\eta }\right) ^{\beta }} }[/math].

This is also referred to as unreliability and designated as [math]\displaystyle{ Q(t) \,\! }[/math] by some authors.

Recalling that the reliability function of a distribution is simply one minus the cdf, the reliability function for the 3-parameter Weibull distribution is then given by:

[math]\displaystyle{ R(t)=e^{-\left( { \frac{t-\gamma }{\eta }}\right) ^{\beta }} }[/math]