[R] problem with nls starting values

[Bert Gunter]

My guess:

You probably are overfitting your data. A straight line does about as
well as anything except for the 3 high leverage points, which the
minimization is probably having trouble with.

-- Bert



On Thu, Sep 27, 2012 at 10:43 AM, Benedikt Gehr
<benedikt.gehr at ieu.uzh.ch> wrote:
> quantiles<-c(seq(.05,.95,0.05))
> slopes<-c( 0.000000e+00,  1.622074e-04 , 3.103918e-03 , 2.169135e-03 ,
> 9.585523e-04
> ,1.412327e-03 , 4.288103e-05, -1.351171e-04 , 2.885810e-04 ,-4.574773e-04
> , -2.368968e-03, -3.104634e-03, -5.833970e-03, -6.011945e-03, -7.737697e-03
> , -8.203058e-03, -7.809603e-03, -6.623985e-03, -9.414477e-03)
> plot(slopes~quantiles)



-- 

Bert Gunter
Genentech Nonclinical Biostatistics

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