[R] non linear regression with R

[Sophie Gerber]

Dear Colleagues,

I have x, y data (pollen and seed dispersal from oaks !) that I would 
like to fit with a function which look like this:

p(a,b,x,y)=b/(2*pi*a²gamma(2/b))*exp(-(square_root(x²+y²)/a)power(b))

I am looking for a and b values that fit my data at best.
Can someone give me hints to perform such an analysis with R ?

Thanks a lot

Sophie


     Sophie Gerber                      gerber at pierroton.inra.fr
      INRA - UMR BIOGECO
      69 route d'Arcachon               tel (33) (0)5 57 12 28 30
      33612 Cestas cedex                fax (33) (0)5 57 12 28 81
       http://www.pierroton.inra.fr/genetics/Perso/Sophie/
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