--- Joseph Wagner <[email protected]> wrote:
> 2. In terms of functional forms, by including a quadratic term our
> simple model (using a measurement, age, and the square of age fits
> well.
The growth is just the first derivative with respect to age, so you can
just create a variable containing the growth and use -sum- to see the
maximum.
gen growth = _b[age] + 2*_b[age2]*age
sum growth
Notice that it is a charateristic of your parameterization that the
maximum growth will occur at the edges (when the subjects are youngest
and oldest), and I am not sure if that is desirable if you are
explicitly interested in finding out when the growth is fastest.
Hope this helps,
Maarten
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
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