curve fit
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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