>>
> 
> Um, a quadratic fit with only three points will ALWAYS fit those three
> points exactly.  When your fit model has the same number of points as your
> data set, the model will always fit exactly and yet will be basically
> meaningless.  Or to be more blunt, the parabola found here is no more
> meaningful than the line you'd get from fitting a set of two points.  It
> might be the best you can do, given the limited data set, but there's no
> reason to believe it reflects the underlying structure.
> 

Oh sorry about that, I wasn't thinking. :(  It takes 2 points to define 
a line and 3 for a parabola, how could I have forgetten. :(

Brendan

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