Dear Statalisters,
Here is my case: I want to model recall bias in retrospective surveys,
looking at the length of the recall period (i.e. distance between the events
reconstructed and the interview) and I was suggested to try to use a spline
model.
I have some theories concerning the shape of the recall (i.e. for example I
may think that from 10 years onwards it doesn't make any difference how much
the time distance to the interview is), but I know it should be somehow
possible to get the number and the position of knots which better describe
what's going on, besides the shape of the effect.
I have been reading a bit about spline models in Stata and I have tried
something (mainly mkspline) but I am quite confused. Which command/procedure
should I look at for doing something like this in Stata? (I mean how to
define the number and the position of knots, and their shape).
Thanks in advance.
Best,
Anna
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