Apologies, but I don't see a question here ... am I missing something
obvious?
Andrew
On Thu, May 05, 2011 at 01:20:33AM -0700, sterlesser wrote:
> ID1 ID2 t V(t)
> 1 1 0 6.053078443
> 2 1 0.3403 5.56937391
> 3 1 0.4181 5.45484486
> 4 1 0.4986 5.193124598
> 5 1 0.7451 4.31386722
> 6 1 1.0069 3.645422269
> 7 1 1.5535 3.587710965
> 8 1 1.8049 3.740362689
> 9 1 2.4979 3.699837726
> 10 1 6.4903 2.908485019
> 11 1 13.5049 1.888179494
> 12 1 27.5049 1.176091259
> 13 1 41.5049 1.176091259
>
> The model
> (1) V(t)=V0[1-epi+ epi*exp(-c(t-t0))]
> (2) V(t)=V0{A*exp[-lambda1(t-t0)]+(1-A)*exp[-lambda2(t-t0)]}
>
> in formula (2) lambda1=0.5*{(c+delta)+[(c-delta)^2+4*(1-epi)*c*delta]^0.5}
>
> lambda2=0.5*{(c+delta)-[(c-delta)^2+4*(1-epi)*c*delta]^0.5}
> A=(epi*c-lambda2)/(lambda1-lambda2)
>
> The regression rule :
> for formula (1):(t<=2,that is) first 8 rows are used for non-linear
> regression
> epi,c,t0,V0 parameters are obtained
> for formula (2):all 13 rows of results are used for non-linear regression
> lambda1,lambda2,A (with these parameters, delta can be calculated from them)
>
> Thanks for help
> Ster Lesser
>
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--
Andrew Robinson
Program Manager, ACERA
Department of Mathematics and Statistics Tel: +61-3-8344-6410
University of Melbourne, VIC 3010 Australia (prefer email)
http://www.ms.unimelb.edu.au/~andrewpr Fax: +61-3-8344-4599
http://www.acera.unimelb.edu.au/
Forest Analytics with R (Springer, 2011)
http://www.ms.unimelb.edu.au/FAwR/
Introduction to Scientific Programming and Simulation using R (CRC, 2009):
http://www.ms.unimelb.edu.au/spuRs/
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