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

dave fournier davef at otter-rsch.com
Tue Oct 25 18:29:08 CEST 2016

  Unfortunately this problem does not appear to be well posed.

     Retention = (b0*Area^(th+1))^b

If b0, th, and b are the parameter only the product (th+1)*b is determined.

This comes from noting that powers satisfy

     (a^b)^c  =  a^(b*c)

So your model can be written as

           (b0^b) * Area^((th+1)*b)

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