Re: StartingParameters
- To: mathgroup at smc.vnet.net
- Subject: [mg16477] Re: [mg16447] StartingParameters
- From: "Kevin J. McCann" <kevinmccann at Home.com>
- Date: Tue, 16 Mar 1999 03:59:37 -0500
- Sender: owner-wri-mathgroup at wolfram.com
Try this: (Example from the book)
<< Statistics`NonlinearFit`
data = {{1.0, 1.0, .126}, {2.0, 1.0, .219},
{1.0, 2.0, .076}, {2.0, 2.0, .126}, {.1, .0, .186}};
(* Note the starting values of 3,10,1 for theta1, theta2, theta3 *)
(* Default values = 1,1,1 *)
NonlinearRegress[data,
theta1 theta3 x1 / (1 + theta1 x1 + theta2 x2),
{x1, x2}, {{theta1,3}, {theta2,10}, {theta3,1}},
RegressionReport -> {BestFitParameters,StartingParameters},
ShowProgress -> True]
Kevin
-----Original Message-----
From: Katarina Midelfort <midelfor at uiuc.edu>
To: mathgroup at smc.vnet.net
Subject: [mg16477] [mg16447] StartingParameters
>Hello,
> I am trying to use the option of giving starting parameters for a
>NonlinearRegress command. I can't figure out the correct syntax for
>this. Can anyone let me know the correct way to list the starting values
>for two parameters in NonlinearRegress (or I think it should be the same
>as NonlinearFit also)
>
>Here is what I am trying:
>NonlinearRegress[datatable, p[t], t ,{kon, koff}, StartingParameters ->
>{{kon, 0.2},{koff,10^8}}]
>
>I would like to have the data in the table (datatable) fit to the model
>( p[t]) with the variables ( t) and the parameters ( kon and koff)
>staring at 0.2 for kon and 10^8 for koff. It doesn't fit when I try
>without giving the starting parameters. What is the correct way to put
>the starting parameters in the above statement?
>
>I hope this question makes sense. Any help is greatfully appreciated.
>
>Thank you,
> Katarina
>
>Katarina Midelfort
>Center for Biophysics and Computational Biology
>University of Illinois
>midelfor at uiuc.edu
>
>