[R] info

[Andrea Calandra]

HI

I'm a student in chemical engineering, 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

Hi 
Mr. Calandra