Paul Velleman wrote:
> > I'd rather fit log(wt) on day.
and Donald Burrill responded:
> Agreed. (Any day!-)
> This has the further virtue of permitting "doubling time" to be
> defined and estimated, for the range in which the exponential growth
> function appears to be an adequate description. (Exponential growth
> always eventually comes to be dominated by some limiting factor(s)
> inherent either in the system exhibiting such growth or in the
> environment in which it takes place. Extrapolation is no more to be
> trusted for such a model than for a polynomial.)
In which case something like A exp{Bt}/(C+exp{Bt}) allowing both
transitions to be modelled would seem ideal.
-Robert
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