Re: weibull plot on weibull scaled paper

*To*: mathgroup at smc.vnet.net*Subject*: [mg116586] Re: weibull plot on weibull scaled paper*From*: DrMajorBob <btreat1 at austin.rr.com>*Date*: Mon, 21 Feb 2011 04:19:36 -0500 (EST)

ProbabilityScalePlot often throws a FindRoot::jsing error with random data, and I wonder why. I'm also trying to see the relationship between these two graphs: dist = WeibullDistribution[7, 200]; Quiet@ProbabilityScalePlot[data, "Weibull"] QuantilePlot[data, dist] Bobby On Sun, 20 Feb 2011 04:25:48 -0600, Bob Hanlon <hanlonr at cox.net> wrote: > > Just label the y-axis with values of the CDF that correspond to the - > Log[1 - CDF[dist, x]] values > > dist = WeibullDistribution[7, 200]; > > LogLogPlot[-Log[1 - CDF[dist, x]], {x, 70, 300}, > Frame -> True, Axes -> False, > FrameTicks -> {Automatic, {-Log[1 - #], > 100 #} & /@ > ({1, 5, 10, 25, 50, 75, 90, 99}/100)}, > PlotRange -> (-Log[1 - #] & /@ {0.005, 0.999})] > > > Bob Hanlon > > ---- Fred Schenkelberg <fms at garlic.com> wrote: > > ============= > Hi Bob, > > Thanks for the response. > > The loglog plot is similar to the classic weibull scales plotted when > using ProbabilityScalePlot, yet isn't the same. For the CDF the vertical > scale should go from near zero to near 100% (or 1 by some authors) > > When using just, > ProbabilityScalePlot[data, "Weibull"] > > from your example - the scales loo right. > > And, I'm pretty sure that I can update the output to include labels, > classic grid lines, etc. > > The problem is that I've not been able to find a way to plot the > 'straight line' representing the known distribution on the weibull > probability paper scales, without having to use RandomVariate and fit a > line. If that is the only way to get to the probability scaled paper, > then, is it possible to plot only the fitted line or reference and not > the data points? > > > In my case, I have the weibull parameters, and not the data. > > It's one of those problems that should be easy.... > > any ideas? > > cheers, > > Fred > > > On Feb 19, 2011, at 5:45 AM, Bob Hanlon wrote: > > > The distribution is just a straight line > > dist = WeibullDistribution[7, 200]; > > llp = LogLogPlot[-Log[1 - CDF[dist, x]], {x, 70, 300}, > Frame -> True, Axes -> False] > > For comparison > > data = RandomVariate[dist, 300]; > > Show[llp, ProbabilityScalePlot[data, "Weibull"]] > > > Bob Hanlon > > ---- Frederick <fms at garlic.com> wrote: > > ============= > Hi, Is it possible to plot > > Plot[Evaluate[CDF[WeibullDistribution[7, 200], x]], {x, 0, 300}] > > using the classic weibull scaled paper, as available in > ProbabilityScalePlot? > > and, without having to plot and/or show data dots.... > > Looking for just a smooth plot of the known distribution on the > classic weibull scaled graph > > thanks, > > Fred > > -- DrMajorBob at yahoo.com