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3P-Weibull Rank Regression
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This example validates the calculations for 3-parameter Weibull with rank regression in Weibull++ standard folios.
Reference Case
Table 6.3 on page 292 in the book Reliability Engineering Handbook Vol 1 by Dr. Kececioglu, Prentice-Hall, 1991.
Data
| Num. in State
|
State F or S
|
Time to Failure
|
| 1 |
F |
46
|
| 1 |
F |
64
|
| 1 |
F |
83
|
| 1 |
F |
105
|
| 1 |
F |
123
|
| 1 |
F |
150
|
| 4 |
S |
200
|
Result
In the book, the results are obtained by visually fitting a straight line to the median rank at each failure point. The reliability function for a 3P-Weibull distribution is:
- [math]\displaystyle{ R(t)=e^{-\left({\frac{t-\gamma }{\eta}}\right )^{\beta }}\,\! }[/math]
The results are [math]\displaystyle{ {\beta}\,\! }[/math] = 1.2, [math]\displaystyle{ {\eta}\,\! }[/math] = 144 and [math]\displaystyle{ {\gamma}\,\! }[/math] = 30
Results in Weibull++
