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| '''Published 3P Weibull Distribution Probability Plot Example'''
| | #REDIRECT [[Weibull Distribution Examples]] |
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| Suppose we want to model a left censored, right censored, interval, and complete data set, consisting of 274 units under test of which 185 units fail. The following Table contains the data.
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| {| {| border="1" class="wikitable" style="margin: 1em auto 1em auto"
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| |+ The Test Data'''
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| | align="center" style="background:#f0f0f0;"|'''Data Point Index'''
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| | align="center" style="background:#f0f0f0;"|'''Number in State'''
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| | align="center" style="background:#f0f0f0;"|'''Last Inspection'''
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| | align="center" style="background:#f0f0f0;"|'''State (S or F)'''
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| | align="center" style="background:#f0f0f0;"|'''State End Time'''
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| |-
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| | 1||2||5||F||5
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| |-
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| | 2||23||5||S||5
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| |-
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| | 3||28||0||F||7
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| |-
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| | 4||4||10||F||10
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| |-
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| | 5||7||15||F||15
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| |-
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| | 6||8||20||F||20
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| |-
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| | 7||29||20||S||20
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| |-
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| | 8||32||0||F||22
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| |-
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| | 9||6||25||F||25
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| |-
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| | 10||4||27||F||30
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| |-
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| | 11||8||30||F||35
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| |-
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| | 12||5||30||F||40
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| |-
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| | 13||9||27||F||45
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| |-
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| | 14||7||25||F||50
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| |-
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| | 15||5||20||F||55
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| |-
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| | 16||3||15||F||60
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| |-
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| | 17||6||10||F||65
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| |-
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| | 18||3||5||F||70
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| |-
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| | 19||37||100||S||100
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| |-
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| | 20||48||0||F||102
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| |-
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| |}
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| '''Solution'''
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| This data set can be entered into Weibull++ by selecting the '''Times-to-failure''' and ''' My data set contains suspensions (right censored data), My data set contains interval and/or left censored data''' and '''I want to enter data in groups options'''.
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| Since standard ranking methods for dealing with these different data types are inadequate, we will want to use the ReliaSoft ranking method. This option is the default in Weibull++ when dealing with interval data.
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| The computed parameters using MLE are:
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| using RRX:
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| and using RRY:
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| The plot with the two-sided 90% confidence bounds for the rank regression on X solution is:
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