Re: [Gretl-users] scripted creation of seasonal dummies
On Sat, 16 Feb 2013, Allin Cottrell wrote:
The doc could do with an update on this sort of thing. In
general "genr x" and "series x" are not equivalent: the former
provokes the error "No formula supplied in genr" while the
latter creates an NA series. As you know, "genr" is (sort of)
deprecated for general use; it's considered better style to
use a specific type-name instead. But... there are a few
specials that are still accomplished via "genr", namely
genr time # linear trend
genr dummy # seasonals
genr unitdum # panel unit dummies
genr timedum # panel period dummies
On Sat, 16 Feb 2013, Allin Cottrell wrote:
I don't have any objection to that, other than the backward
incompatibility. Any others have thoughts on the matter?
We could actually push the idea a little bit further: the following
already works in CVS:
<hansl>
nulldata 24
setobs 4 1:1
q = $obsminor
list D = dummify(q)
setobs 6 1:1 --stacked-time-series
u = $unit
t = time
list U = dummify(u)
list T = dummify(t)
</hansl>
we could deprecate the "genr" special cases Allin cited above in favour of
* the substitution of the "time" special thing with a dollar accessor
called (well, doh) $time;
* allowing dummify to take $obsminor, $unit and $time as arguments.
Now this would be a rather drastic backward-incompatibility, but would
make things more elegant (in the C source too).
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Riccardo (Jack) Lucchetti
Dipartimento di Scienze Economiche e Sociali (DiSES)
Università Politecnica delle Marche
(formerly known as Università di Ancona)
r.lucchetti(a)univpm.it
http://www2.econ.univpm.it/servizi/hpp/lucchetti
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