Template:Example: Median Rank Plot Example: Difference between revisions
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::<math>MR=\frac{1}{1+\left( \frac{10-6+1}{6} \right){{F}_{0.5;10;12}}}</math> | ::<math>MR=\frac{1}{1+\left( \frac{10-6+1}{6} \right){{F}_{0.5;10;12}}}</math> | ||
Use the QSR to calculate the value of F0.50;10;12 = 0.9886, as shown next: | |||
[[Image: F Inverse.png|center|550px]] | [[Image: F Inverse.png|center|550px]] | ||
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::<math>MR=\frac{1}{1+\left( \frac{5}{6} \right)\times 0.9886}=0.5483=54.83%</math> | ::<math>MR=\frac{1}{1+\left( \frac{5}{6} \right)\times 0.9886}=0.5483=54.83%</math> | ||
Another method is to use the Median Ranks option directly, which yields MR(%) = 54.8305%, as shown next: | Another method is to use the '''Median Ranks''' option directly, which yields MR(%) = 54.8305%, as shown next: | ||
[[Image: MR.png|center|550px]] | [[Image: MR.png|center|550px]] |
Revision as of 09:28, 8 August 2012
Median Rank Plot Example
In this example, we will determine the median rank value used for plotting the sixth failure from a sample size of ten. This will be used to illustrate two of the built-in functions in Weibull++'s Quick Statistical Reference.
Solution
First, open the Quick Statistical Reference and select the Inverse F-Distribution Values option.
In this example, N = 10, j = 6, m = 2(10 - 6 + 1) = 10, and n = 2 x 6 = 12.
Thus, from the F-distribution rank equation:
- [math]\displaystyle{ MR=\frac{1}{1+\left( \frac{10-6+1}{6} \right){{F}_{0.5;10;12}}} }[/math]
Use the QSR to calculate the value of F0.50;10;12 = 0.9886, as shown next:
Consequently:
- [math]\displaystyle{ MR=\frac{1}{1+\left( \frac{5}{6} \right)\times 0.9886}=0.5483=54.83% }[/math]
Another method is to use the Median Ranks option directly, which yields MR(%) = 54.8305%, as shown next: