Template:Three-parameter weibull distribution: Difference between revisions
Jump to navigation
Jump to search
No edit summary |
Lisa Hacker (talk | contribs) No edit summary |
||
| Line 3: | Line 3: | ||
::<math> f(t)={ \frac{\beta }{\eta }}\left( {\frac{t-\gamma }{\eta }}\right) ^{\beta -1}e^{-\left( {\frac{t-\gamma }{\eta }}\right) ^{\beta }} </math> | ::<math> f(t)={ \frac{\beta }{\eta }}\left( {\frac{t-\gamma }{\eta }}\right) ^{\beta -1}e^{-\left( {\frac{t-\gamma }{\eta }}\right) ^{\beta }} </math> | ||
where | where: | ||
::<math> f(t)\geq 0,\text{ }t\geq 0\text{ or }\gamma, </math> | ::<math> f(t)\geq 0,\text{ }t\geq 0\text{ or }\gamma, </math> | ||
::<math>\beta>0\ \,\!</math> | ::<math>\beta>0\ \,\!</math> | ||
::<math> \eta > 0 \,\!</math> | ::<math> \eta > 0 \,\!</math> | ||
::<math> -\infty < \gamma < +\infty \ | ::<math> -\infty < \gamma < +\infty \\!</math> | ||
and | and: | ||
::<math> \eta= \,\!</math> scale parameter, or characteristic life | ::<math> \eta= \,\!</math> scale parameter, or characteristic life | ||
::<math> \beta= \,\!</math> shape parameter (or slope) | ::<math> \beta= \,\!</math> shape parameter (or slope) | ||
::<math> \gamma= \,\!</math> location parameter (or failure free life) | ::<math> \gamma= \,\!</math> location parameter (or failure free life) | ||
Revision as of 21:08, 30 March 2012
The three-parameter Weibull pdf is given by:
- [math]\displaystyle{ f(t)={ \frac{\beta }{\eta }}\left( {\frac{t-\gamma }{\eta }}\right) ^{\beta -1}e^{-\left( {\frac{t-\gamma }{\eta }}\right) ^{\beta }} }[/math]
where:
- [math]\displaystyle{ f(t)\geq 0,\text{ }t\geq 0\text{ or }\gamma, }[/math]
- [math]\displaystyle{ \beta\gt 0\ \,\! }[/math]
- [math]\displaystyle{ \eta \gt 0 \,\! }[/math]
- [math]\displaystyle{ -\infty \lt \gamma \lt +\infty \\! }[/math]
and:
- [math]\displaystyle{ \eta= \,\! }[/math] scale parameter, or characteristic life
- [math]\displaystyle{ \beta= \,\! }[/math] shape parameter (or slope)
- [math]\displaystyle{ \gamma= \,\! }[/math] location parameter (or failure free life)