Regress Nonlinear Equation
Nov 20, 2008
Below is a nonlinear model, together with calibration data for which I would like to find the parameters Ro, Kc, a and b.
R = Ro + Kc * (1/(1 + exp(-(a + b*lnC))
Calibration Data
C R
0.00.3347
4.80.4201
7.70.5141
11.20.6177
14.40.6887
Given the calibration data above, how can I calculate or at least estimate these parameters?
I do not want to use an add-in program, like Solver, in Excel. I do, however, want to be able to use any existing functions, if necessary, in Excel. i'd appreciate it if someone can walk me through the steps.
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Feb 5, 2008
i just recorded a macro to perform regression using the Data Analysis Tool in Excel. But gives me error message: "Y Input Range missing. Please Enter"
X range: A9:A90
Y range: B9:C90
But instead of capturing these ranges during recording, this is the code actually recorded:
Application.Run "ATPVBAEN.XLA!Regress", , , False, True, , "", False _
, False, False, False, , False
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