Sorry I'm student in biomedical engineer and i have to solve this formula for immuno-assay. I need to design a calibration curve
But i don't understand How can i write this formula in R language: y = a + (c - a) /(1+ e[-b(x-m]) where x = ln(analyte dose + 1) y = the optical absorbance data a = the curves top asymptote b = the slope of the curve c = the curves bottom asymptote m = the curve X intercept I have to calculate the parameters (a,b,c,m).After with X that i know i calculate the Y. > ========================== > Date: Tue, 15 Jul 2003 19:30:31 -0700 (PDT) > From: Rick Fletcher <[EMAIL PROTECTED]> > To: Andrea Calandra <[EMAIL PROTECTED]> > Subject: Re: Info > ========================== > > > Andrea, if you only have five data points, it will be very difficult > to > fit all those parameters so they give a unique solution. If > you want to > fit all of your parameters at once, you need many more data points. > > On Tue, 15 Jul 2003, Andrea Calandra wrote: > > > downloaded the R Language, it's very good! > > but i have a question > > > > i have Five point with X and Y that know (concentration and > optical density) how can interpolate the curve > > with folowing FIVE INTERPOLATION > > > > y = a + (c - a) /(1+ e[-b(x-m]) > > > > > > > > where > > > > x = ln(analyte dose + 1) > > > > y = the optical absorbance data > > > > a = the curves top asymptote > > > > b = the slope of the curve > > > > c = the curves bottom asymptote > > > > m = the curve X intercept > > > > > > > > > > > > > > > > > ========================== > > > Date: Mon, 07 Jul 2003 11:11:28 -0700 (PDT) > > > From: Rick Fletcher <[EMAIL PROTECTED]> > > > To: Andrea Calandra <[EMAIL PROTECTED]> > > > Subject: Re: Info > > > ========================== > > > > > > Did you find a solution yet? I am sorry for the delay in > response, > > > but > > > the July 4th weekend is a big holiday here. It is the day > we > > > celebrate > > > our independence from England. > > > > > > Do you still need help? > > > > > > > > > On Fri, 4 Jul 2003, Andrea Calandra wrote: > > > > > > > i take your name on the web! > > > > thank you > > > > > > > > > ========================== > > > > > Date: Thu, 03 Jul 2003 11:05:24 -0700 (PDT) > > > > > From: Rick Fletcher <[EMAIL PROTECTED]> > > > > > To: Andrea Calandra <[EMAIL PROTECTED]> > > > > > Subject: Re: Info > > > > > ========================== > > > > > > > > > > > > > > > Hello, > > > > > > > > > > May I ask how you got my name? Thank you. > > > > > > > > > > > > > > > On Thu, 3 Jul 2003, Andrea Calandra wrote: > > > > > > > > > > > HI > > > > > > > > > > > > I'm a student in chemical engineering at university > of > > > Rome, > > > > > and i have to implement an algoritm about FIVE PARAMETERS > > > INTERPOLATION > > > > > for a calibration curve (dose, optical density) > > > > > > > > > > > > y = a + (c - a) /(1+ e[-b(x-m]) > > > > > > > > > > > > where > > > > > > x = ln(analyte dose + 1) > > > > > > y = the optical absorbance data > > > > > > a = the curves top asymptote > > > > > > b = the slope of the curve > > > > > > c = the curves bottom asymptote > > > > > > m = the curve X intercept > > > > > > > > > > > > Have you never seen this formula, because i don't fine > > > information > > > > > or > > > > > > lecterature about solution of this!!! > > > > > > > > > > > > Can i help me > > > > > > Andrea Calandra > > > > > > > > > > > > thank you > > > > > > > > > > > > > > > > > > > > > > > > > > > > Rick > > > > > T. Rick Fletcher - http://www.chem.uidaho.edu/~fletcher/ > > > > > Associate professor of chemistry | That's Idaho, not > Iowa. > > > > > | ad hominem > > > > > University of Idaho | Upper Left Hand > Corner. > > > > > | ad hominem > > > > > Moscow, ID 83844-2343 | No, I don't grow > potatoes. > > > > > | ad hominem > > > > > > > > > > > > > > > > > > Rick > > > T. Rick Fletcher - http://www.chem.uidaho.edu/~fletcher/ > > > Associate professor of chemistry | That's Idaho, not Iowa. > > > | ad hominem > > > University of Idaho | Upper Left Hand Corner. > > > | ad hominem > > > Moscow, ID 83844-2343 | No, I don't grow potatoes. > > > | ad hominem > > > > > > > > Rick > T. Rick Fletcher - http://www.chem.uidaho.edu/~fletcher/ > Associate professor of chemistry | That's Idaho, not Iowa. > | ad hominem > University of Idaho | Upper Left Hand Corner. > | ad hominem > Moscow, ID 83844-2343 | No, I don't grow potatoes. > | ad hominem ______________________________________________ [EMAIL PROTECTED] mailing list https://www.stat.math.ethz.ch/mailman/listinfo/r-help