[R] Optimization

From: Simone Vincenzi <svincenz_at_nemo.unipr.it>
Date: Wed 30 Aug 2006 - 23:56:50 EST

Dear R-list,
I'm trying to estimate the relative importance of 6 environmental variables in determining clam yield. To estimate clam yield a previous work used the function Yield = (A^a*B^b*C^c...)^1/(a+b+c+...) where A,B,C... are the values of the environmental variables and the weights a,b,c... have not been calibrated on data but taken from literature. Now I'd like to estimate the weights a,b,c... by using a dataset with 110 observations of yield and values of the environmental variables. I'm wondering if it is feasible or if the number of observation is too low, if some data transformation is needed and which R function is the most appropriate to try to estimate the weights. Any help would be greatly appreciated.

Simone Vincenzi

Simone Vincenzi, PhD Student
Department of Environmental Sciences
University of Parma
Parco Area delle Scienze, 33/A, 43100 Parma, Italy Phone: +39 0521 905696
Fax: +39 0521 906611
e.mail: svincenz@nemo.unipr.it

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Received on Thu Aug 31 00:07:25 2006

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