[R] curve fit

[Gabor Grothendieck]

y ~ 1/(a + b*x^c) looks pretty good to me.

If we assume a starting value of c=1 then we can get
the starting values of a and b from lm(1/y ~ x) and
then do an nls fit.

On 10/20/05, Xiaodong Jin <close2ceo at yahoo.com> wrote:
> How to obtain the FUNCTION for the following smooth curve?
> x 0    100 250 500 1000  4000
> y 1.8  1.2 1.02 0.99 0.97 0.85
>
> Thanks,
> SJ
>
>
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