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I am trying to reproduce a ProbabilityScalePlot of censored data shown here (see Sample Analysis Plot). Here is my Mathematica code. First I deal with the uncensored case.

probscaleplotFix = 
Graphics[Append[First@#, Epilog /. Options[#, Epilog]], 
FilterRules[Options[#], Except[Epilog]]] &;
SetOptions[ProbabilityScalePlot, 
DisplayFunction -> 
probscaleplotFix]; (* Needed to fix a software bug, see solution \
by Alexey Popkov on StackExchange *)

data = {30, 49, 82, 90, 96};
distA = EstimatedDistribution[data, 
WeibullDistribution[a, b], {{a, 3}, {b, 50}}]
plot1 = Plot[PDF[distA, t], {t, 0, 200}, Frame -> True, 
FrameLabel -> {"Time", "PDF"}, 
PlotLabel -> "Distribution 1 (no censoring)", PlotRange -> All, 
PlotStyle -> Red]

Plot 1

plot2 = ProbabilityScalePlot[data, "Weibull", 
PlotRange -> {{10, 200}, {1, 90}}, PlotStyle -> Red, Frame -> True, 
FrameLabel -> {"Time", "CDF"}, 
PlotLabel -> 
"ProbabilityScalePlot for Distribution 1 (no censoring)", 
GridLines -> Automatic]

Plot 2

So far so good . . . now for the censored data.

eventdata = 
EventData[{30, 49, 82, 90, 96, 10, 45, 100}, {None, None, None, None,
None, Right, Right, Right}]

dist2 = EstimatedDistribution[eventdata, 
WeibullDistribution[a2, b2], {{a2, 3}, {b2, 50}}]

plot3 = Plot[PDF[dist2, t], {t, 0, 200}, Frame -> True, 
FrameLabel -> {"Time", "PDF"}, 
PlotLabel -> "Distribution 2 (censoring)", PlotRange -> All]

Plot 3

plot4 = ProbabilityScalePlot[dist2, "Weibull", 
PlotRange -> {{1, 100}, {1, 99}}, PlotStyle -> Blue, Frame -> True, 
FrameLabel -> {"Time", "CDF"}, 
PlotLabel -> "ProbabilityScale Plot for Distribution 2 (censoring)"]

ProbabilityScalePlot::estmd: Unable to estimate a reference distribution from the data. >>

plot5 = ProbabilityScalePlot[eventdata, "Weibull", 
PlotRange -> {{1, 100}, {1, 99}}, PlotStyle -> Blue, Frame -> True, 
FrameLabel -> {"Time", "CDF"}, 
PlotLabel -> "ProbabilityScale Plot for Distribution 2 (censoring)"]

ProbabilityScalePlot::ldata: EventData[8] is not a valid dataset, distribution, or a valid list of datasets and distributions. >>

Can someone tell me how to produce the ProbabilityScalePlot for either eventdata or dist2 ?

Many Thanks.

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ProbabilityScalePlot doesn't support censored data for now. However, you can plot censored data as regular data

ProbabilityScalePlot[eventdata["InputData"], "Weibull", 
  PlotRange -> {{1, 100}, {1, 99}}, PlotStyle -> Blue, Frame -> True, 
  FrameLabel -> {"Time", "CDF"}, 
  PlotLabel -> "ProbabilityScale Plot for Distribution 2 (censoring)"]

enter image description here

Or extract data without censoring

ProbabilityScalePlot[
 Pick[eventdata["InputData"], eventdata["CensoringIndicators"], 0], 
 "Weibull", PlotRange -> {{1, 100}, {1, 99}}, PlotStyle -> Blue, 
 Frame -> True, FrameLabel -> {"Time", "CDF"}, 
 PlotLabel -> "ProbabilityScale Plot for Distribution 2 (censoring)"]

enter image description here

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  • $\begingroup$ much appreciated, your solution meets my needs. $\endgroup$ – Steve Sep 27 '13 at 23:54

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