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| '''Normal Distribution General Example Interval Data'''
| | #REDIRECT[[Normal_Distribution_Examples#Interval_Censored_Data]] |
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| Eight units are being reliability tested and the following is a table of their times-to-failure:
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| {|align="center" border=1 cellspacing=1
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| |-
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| |colspan="3" style="text-align:center"| Table - Non-Grouped Data Times-to-Failure with intervals (lnterval and left censored)
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| |-
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| !Data point index
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| !Last Inspected
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| !State End Time
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| |-
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| |1 ||30||32
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| |-
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| |2 ||32||35
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| |-
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| |3 ||35||37
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| |-
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| |4 ||37||40
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| |-
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| |5 ||42||42
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| |-
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| |6 ||45||45
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| |-
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| |7||50||50
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| |-
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| |8||55||55
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| |}
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| '''Solution'''
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| This is a sequence of interval times-to-failure. This data set can be entered into Weibull++ by creating a data sheet that can be used to analyze times-to-failure data with interval and left censored data.
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| <math></math>
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| [[Image:lastinspected.png|thumb|center|400px| ]] | |
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| [[Image:lastinspectedsheet.png|thumb|center|400px]]
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| The computed parameters for maximum likelihood are:
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| ::<math>\begin{align}
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| & \widehat{\mu }= & 41.40 \\
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| & {{{\hat{\sigma }}}_{T}}= & 7.740.
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| \end{align}</math>
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| For rank regression on x:
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| ::<math>\begin{align}
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| & \widehat{\mu }= & 41.40 \\
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| & {{{\hat{\sigma }}}_{T}}= & 9.03.
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| \end{align}</math>
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| For rank regression on y:
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| ::<math>\begin{align}
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| & \widehat{\mu }= & 41.39 \\
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| & {{{\hat{\sigma }}}_{T}}= & 9.25.
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| \end{align}</math>
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| A plot of the MLE solution is shown next.
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| <math></math>
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| [[Image:lastinspectedplot.png|thumb|center|400px| ]]
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