## Propability plots

Ideas and wishes for TeeChart
Newbie
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Joined: Fri Nov 15, 2002 12:00 am

### Propability plots

I need propability plots to show a normal distribution or a weibull distribution and so on.

Greetings Heinz

Marjan
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Location: Slovenia
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Hi, Heinz.

Using the latest TeeChart version which supports custom axis labels (text and position for individual labels) implementing any non-linear plot should be easy. All you need is transformation for values and labels.

I've implemented it for normal, Weibull and Q-Q plots. I'll prepare an article about this shortly and post it here.

epidata
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### qq plots etc

When is shortly (mentioned in 2003 november ) ?

Marjan
Posts: 745
Joined: Fri Nov 07, 2003 5:00 am
Location: Slovenia
Contact:
Hi.

Sorry about (long) delay. I've implemented some of the probabilities plots (among other addditional statistical charts) for another statistical library I'm working on. Some images are available at http://www.dewresearch.com/StatsSeriesGallery.html. In case you're interested I can send you full C# sources (for TeeChart .NET).
Marjan Slatinek,
http://www.steema.com

epidata
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### probability plots with teechart

I have now implemented probability plots in EpiData using a standard point series of teechart. The sequence is:
1. create a series with cumulative percentages
.. xvalues cumpercentage
2. convert to probabilities, e.g. see
.. xvalues cumprob
Bland M: Introduction to Medical Statistics. Oxford, 2nd ed. p 112.
3. find an inverse normal function for the probabilites
yvalue = inverse normal (cumprob)
(search internet for "normal probability .....source code", you will get several hits., e.g. "normal probability pascal source"
4. create a standard TChart with a pointseries and do a addxy(xvalues yvalue) and you have the normal probability plot
example:

FrancisP
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Joined: Mon Jul 04, 2005 4:00 am
Marjan wrote:Hi.

Sorry about (long) delay. I've implemented some of the probabilities plots (among other addditional statistical charts) for another statistical library I'm working on. Some images are available at http://www.dewresearch.com/StatsSeriesGallery.html. In case you're interested I can send you full C# sources (for TeeChart .NET).
Marjan,
I would be very interested in the QQ-plot code. Would you be able to send me a copy?
Cheers
Francis

Narcís