When constructing the predicted curve uses values that you already have for the parameters that you want to predict, it doesn't really help to fit a curve to data when you don't have those values, in a normal situation. It would be much more useful to know how to do this when you do not have the values at the start of the operation.
By "in my opinion" I mean: my educated guess (actually based on the least-squares method). You have to come up with the value for these 3 or 4 parameters and then use them in your formulas. I came up with 2.12 for the slope (a1), so you have to type that value in cell B2. You can also download the file (see below) or use my 2013 book or CD.
Hello! I know this video was posted a long time ago but by chance do you still have the excel file available? I tried the link you posted in the comments but it seems to not work. Could you potentially post a new link to the excel file or send it to my email.
Hi, I was trying to finde ic50 with a 4PL, but my results dosen't mach with what I have from a friend (I don't know how he make it). I do solve de sum of squars, But I don´t have the same values. It is 4PL good for doing that? Tyvm.
Thanks a lot for the explanation! But how must I modify the boltzmann fit (or change the Excel calculation) if I need a boltzmann fit with a free (not fixed) minimum calculation for a unknown value (have a fixed top at 100%)? I only get somthing comparable (with other statistical programs like GraphPad Prism) if I subtract the last value minus the difference of the penultimate value from the last datapoint. means(%): y(unknown)=60-(70-60)
I´ve find a solution by myself; added the minimum (last known value) to solver, it calculates for all parameters the smallest values. Now it´s 100% comparable to known statistic programs.
Good evening Dr Gerard Verchuuren. really excellent ways how to know the IC50. could you teach me how to get the value of SP, slope (a1) and IP? thank you ^_^
Good afternoon Dr Verschuuren, I am sure this point has already been discussed, but I do not realized how do you determine the IP, slope and SP in the beggining of the analysis to construct the prediction. Also, where could this file be found to use as a guide? Thanks you very much. Vanina Castroagudin
***** It's still there. Make sure to type the address exactly as given. The only problem could be that some browsers tell you there is a virus in it (because of VBA code). Then try another browser. The file is safe!
Great doc! you have provided the spread sheet free of cost for use of everyone.
Thanks a lot.
When constructing the predicted curve uses values that you already have for the parameters that you want to predict, it doesn't really help to fit a curve to data when you don't have those values, in a normal situation. It would be much more useful to know how to do this when you do not have the values at the start of the operation.
How were the IP, Slope, and SP calculated?
By "in my opinion" I mean: my educated guess (actually based on the least-squares method). You have to come up with the value for these 3 or 4 parameters and then use them in your formulas. I came up with 2.12 for the slope (a1), so you have to type that value in cell B2.
You can also download the file (see below) or use my 2013 book or CD.
The file is certainly available. Make sure the file extension at the end is not xlsx but zip.
Ah yes, very good, Dr. That was exactly the problem. I have the spreadsheet before me now. Thank you.
Hello! I know this video was posted a long time ago but by chance do you still have the excel file available? I tried the link you posted in the comments but it seems to not work. Could you potentially post a new link to the excel file or send it to my email.
Does anyone have an updated version? This one won't open in the latest excel version.
I done an drug response experiment and I want to know how can I produce a sigmoidal curve on excel with the results I had obtained.
Greetings Gerard,
Is it possible to download a copy of the excel file you have used in this video so I can study it more closely?
Hi, I was trying to finde ic50 with a 4PL, but my results dosen't mach with what I have from a friend (I don't know how he make it). I do solve de sum of squars, But I don´t have the same values. It is 4PL good for doing that? Tyvm.
Thanks a lot for the explanation! But how must I modify the boltzmann fit (or change the Excel calculation) if I need a boltzmann fit with a free (not fixed) minimum calculation for a unknown value (have a fixed top at 100%)? I only get somthing comparable (with other statistical programs like GraphPad Prism) if I subtract the last value minus the difference of the penultimate value from the last datapoint. means(%): y(unknown)=60-(70-60)
I´ve find a solution by myself; added the minimum (last known value) to solver, it calculates for all parameters the smallest values. Now it´s 100% comparable to known statistic programs.
Good evening Dr Gerard Verchuuren. really excellent ways how to know the IC50. could you teach me how to get the value of SP, slope (a1) and IP? thank you ^_^
see my video ruclips.net/video/q8ldtlm8BbA/видео.html
Thanks a bunch for helping me with your video. God bless u ^_^
Good afternoon Dr Verschuuren, I am sure this point has already been discussed, but I do not realized how do you determine the IP, slope and SP in the beggining of the analysis to construct the prediction. Also, where could this file be found to use as a guide? Thanks you very much.
Vanina Castroagudin
For more details, see my book: www.mrexcel.com/store/index.php?l=product_detail&p=292.
For the file, see comments below on his page.
Hey, I can't seem to find the file... Is it still in the comments below?
***** It's still there. Make sure to type the address exactly as given. The only problem could be that some browsers tell you there is a virus in it (because of VBA code). Then try another browser. The file is safe!
hi, whats mean of compound in video? that can be percent of cell viability ?
File is no longer available? Link dead?
How do you mean, "the slope, in your opinion" at time=2:02 ? My output gives me the inflexion point, but no slope :(
Thanks for the video!
can someone please tell me how i calculate the LD50 using graphpad prism??? i have no idea how to use it
I can't seem to see the link to the file? Is it still available?
www.genesispc.com/download/EC50.zip
Dr. Gerard Verschuuren Thank you!
Thank you very much!
How can I reference this method?
bonjour tu peux m'aider comment on calcule la concentration dans l'activite dpph
I should have created a zip file from the xlsx file. So change the last extension (xlsx) into zip
Hello, I can't seem to find the file !... Is it still available ? I hope your help please !
+Djida Ayad It certainly is. Ask someone to check your spelling:
www.genesispc.com/download/EC50.zip