Test-Fix-Test Data Reference Example: Difference between revisions

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::<math>\begin{align}
::<math>\begin{align}
\hat{\beta }=&\frac{N}{{N\ln T^{*}}-\sum_{i=1}^{N}T_{i}}\\
\widehat{\beta }=&\frac{N}{{N\ln T^{*}}-\sum_{i=1}^{N}T_{i}}\\
\\
\\
=&\frac{23}{{23\cdot \ln \left ( 500 \right )}-87.2106}\\
=&\frac{23}{{23\cdot \ln \left ( 500 \right )}-87.2106}\\
Line 84: Line 84:


::<math>\begin{align}
::<math>\begin{align}
\hat{\lambda }=&\frac{N}{T^{*\beta }}\\
\widehat{\lambda }=&\frac{N}{T^{*\beta }}\\
\\
\\
=&\frac{23}{500^{0.4127}}\\
=&\frac{23}{500^{0.4127}}\\

Revision as of 22:42, 12 June 2014

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RGA_Reference_Examples

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

0.2
4.2
4.5
5
5.4
6.1
7.9
14.8
19.2
48.6
85.8
108.9
127.2
129.8
150.1
159.7
227.4
244.7
262.7
315.3
329.6
404.3
486.2
Termination Time = 500 hours


Result

Beta = 0.413, Lambda = 1.769

DMTBF = 52.7

Confidence Bounds on DMTBF (CL = 80%) = (35.6, 82.9)


Results in RGA


[math]\displaystyle{ \begin{align} \widehat{\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]


[math]\displaystyle{ \begin{align} \widehat{\lambda }=&\frac{N}{T^{*\beta }}\\ \\ =&\frac{23}{500^{0.4127}}\\ \\ =&1.7691 \end{align}\,\! }[/math]


CB for Weibull Results.png


CB for Weibull QPC.png