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Test-Fix-Test Data Reference Example
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This example compares the results for test-fix-test data (time terminated).
Reference Case
Crow, L.H., Confidence Interval Procedures for the Weibull Process with Applications to Reliability Growth, U.S. Army Material Systems Analysis Activity, 1981.
Data
Termination Time = 500 hours
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0.2
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4.2
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4.5
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5
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5.4
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6.1
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7.9
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14.8
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19.2
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48.6
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85.8
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108.9
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127.2
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129.8
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150.1
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159.7
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227.4
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244.7
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262.7
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315.3
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329.6
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404.3
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486.2
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Result
Beta = 0.413, Lambda = 1.769
DMTBF = 52.7
Confidence Bounds on DMTBF (CL = 80%) = (35.6, 82.9)
Results in Weibull++
- [math]\displaystyle{ \begin{align}
\hat{\beta }=&\frac{N}{{N\ln T^{*}}-\sum_{i=1}^{N}T_{i}}\\
=&\frac{23}{{23\cdot \ln \left ( 500 \right )}-87.2106}\\
=&0.4127
\end{align}\,\! }[/math]