[R] Finding starting values for the parameters using nls() or nls2()

[Pinglei Gao]

Thanks very much for your kindness help. I run your script then came out
lots of outputs and I also studied the solution you posted. Forgive my
ignorance, I still can't find the suitable starting values. Did I
misunderstand something?

Best,

Pinglei Gao

-----邮件原件-----
发件人: ProfJCNash [mailto:profjcnash at gmail.com] 
发送时间: 2016年10月10日 10:41
收件人: Gabor Grothendieck; Pinglei Gao
主题: Re: [R] Finding starting values for the parameters using nls() or
nls2()

I forgot to post the "solution" found by nlmrt:

nlmrt class object: x
residual sumsquares =  1086.8  on  15 observations
    after  5001    Jacobian and  6991 function evaluations
  name            coeff          SE       tstat      pval      gradient
JSingval
b0            5.3274e-14            NA         NA         NA  -6.614e+13
1.735e+16
b1               33.5574            NA         NA         NA      -3.466
11518
th           -0.00721203            NA         NA         NA      -740.8
0.004635


Note the singular values -- this is the worst SV(max)/SV(min) ratio I've
observed!

JN