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Create a Weibull Chart in Excel 2010

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Jim W.

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Hello Forum,

I am trying to create a Weibull chart in Excel 2010. Not just a standard quantile chart, but a chart that looks like the old timey Weibull paper charts that were used years ago. I have searched google and have not found any help on how to contruct these charts.

I have the data I am working with along with a chart that I have produced so far. My trouble is scaling the Y-axis appropriately. My data, current attempt at plotting is attached. Also attached is an example of the plot I would like to create in my spreadsheet.

Thanks for helping,
Jim
 

Attachments

  • ExampleWeibullAnalysis.xlsx
    13 KB · Views: 43
  • CaptureCurrentPlot.PNG
    CaptureCurrentPlot.PNG
    9.3 KB · Views: 55
  • desiredWeibullPlot.png
    desiredWeibullPlot.png
    156.1 KB · Views: 79
A quick Google search turns up a number of examples and tutorials
https://www.google.com.au/search?q=weibull chart in excel
HUI - Thank you.... I tried google search and came up with a lot of the same links that you came up with. However, most of the plots were simple quantile-quantile charts. I am finding it difficult to make the y-axis print in CDF percentages with the proper logarithmic scale. The plots in those links are not the same and what I would like to generate.

Thanks for the reply,
Kind regards,
Jim
 
Jim

I don't really understand enough about what your doing but I suspect that doing a Ln(Ln()) is causing the issues, as it is creating Y values which are less than 0, which can't be plotted on a Log chart

Should E3 be: =LN(1/(1-C3)) copy down

This enables:
upload_2015-2-20_9-37-34.png
 
Hui

I you caused me to go back and check the math and you are correct but the equation should be -Ln(1-C3). I am uploading what I have to date and it looks like we are getting closer. I found a methodolgy from peltier http://www.excelforum.com/excel-charting-and-pivots/527729-weibull-paper-in-excel-how.html but this really confuses trying to create a custom y-axis.

Please note the data in the example of the desired weibull plot is not the same as in my example. However the plot should look similar.

Thank you Hui and any others who are helping with this problem.

Jim
 

Attachments

  • ExampleWeibullAnalysis.xlsx
    13.5 KB · Views: 26
Hui

I you caused me to go back and check the math and you are correct but the equation should be -Ln(1-C3). I am uploading what I have to date and it looks like we are getting closer. I found a methodolgy from peltier http://www.excelforum.com/excel-charting-and-pivots/527729-weibull-paper-in-excel-how.html but this really confuses trying to create a custom y-axis.

Please note the data in the example of the desired weibull plot is not the same as in my example. However the plot should look similar.

Thank you Hui and any others who are helping with this problem.

Jim

P.S. Hui - I realize Ln(1/1-C3)=-Ln(1-C3) .... ;-)
 
Hows this?
upload_2015-2-20_21-58-37.png

What else do you require ?
 

Attachments

  • ExampleWeibullAnalysis.xlsx
    16.2 KB · Views: 31
Hows this?
View attachment 16037

What else do you require ?

Hui,

That looks really good. I just looked at the link about the special y-axis procedure from Peltier but that does not result in the Weibull plot style. To match what I am looking for, the y-axis values need to have a scale of percentage like 0.001 to 0.999 on a log scale so the plot is relatively linear. I am stuck getting the y-axis to appear like the y-axid in my example of the Weibull plot paper at the beginning of my post. If I can get that scale then we are done.

Thanks Hui,
Jim
 
That's perfect but I appears that the axis is linear instead of logrythmic like in this plot.
 

Attachments

  • desiredWeibullPlot.jpg
    desiredWeibullPlot.jpg
    209.7 KB · Views: 26
Hui,

You truly are an Excel Ninja. Is there anyway I can get the spreadsheet that generates that plot. I would like to label more percentages than 1% 10% and 100% maybe .1%, 1%, 10%, 20% ... 0.80%, 90%, 95% and 99.9%. Would it be difficult for me to do that you think? I hope it isn't too complicated to contruct this chart. Did you have to use any VBA?

Thanks so much,
Jim
 
Its your spreadsheet? In my 2nd last post, with the above instructions applied, but it is also below
No VBA
Not sure about extra grid lines, but give me a day, I have an idea
 

Attachments

  • ExampleWeibullAnalysis.xlsx
    16.8 KB · Views: 30
Hui,

That looks great. Is it complicated to construct? I will save a copy take a look at it and get back to you in a few minutes.

Jim
 
I'll fix that tomorrow

Do you want any of those other diagonal or critical lines in the original file

Difficult to construct , yes if your not very familiar with Excel Charts?
 
Hui,

Thank you so much for helping me with this. I would like to be able to draw the lines. The lines are basicall a linear regression on the transformed data. The Beta scale on the left-most side is not required. I will need the 0.632 dashed line however. Most important is getting the x-axis (looks good) and the y-axis looking and plotting the data properly.

I am sorry to hear that that this chart is difficult to contruct. I would think that Microsoft would have some sort of reliability add-in that would make this easy. When you finished if you could give a short summary to me so that I can regenerate this plot when I have new data that would be greatly appreciated.

Thanks again Hui, and kind regards,
Jim
 
The problem here is getting the axis scaling correct
You will have to manually adjust the Y Axis Minimum and Maximum values manually until you get what is right

Right Click on each axis and select Format Axis
Adjust the Minimum and Maximum Bounds to get the right result

I have added the 63.2% Line
 

Attachments

  • ExampleWeibullAnalysis.xlsx
    18.4 KB · Views: 60
Thank you Hui, I appreciate all of the help. It's tricky to get the scale correct using Excel. I guess that's why Weibull plots are created on other platforms. I will take this last file and work on it some more. You have it very close. If/when I get it in final form I will post it back. I need to scale it so the dots plot in a linear fashion (like on Weibull plot paper). Thanks again for the help.

Jim
 
Excel has limitations here like it can't set a 0 as a base on the Log Scale and seems to round the Upper ends as well, but the approximations cause the errors you see

I may be possible to calculate all values as X,Y and plot as a straight Scatter chart with regular axis, That should be possible.

Maybe when I have a spare day?
 
I finally have what I am looking for.... The Weibull plot is attached to help anyone else who might have a need for this type of plot.

Thank you HUI and all others for any help you provided.

Kind regards,
Jim
 

Attachments

  • WeibullPlot.xlsx
    58.3 KB · Views: 175
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