Re: [Gretl-users] Re: Gretl-users Digest, Vol 21, Issue 9
On Fri, 13 Jan 2006, Allin Cottrell wrote:
On Sat, 14 Jan 2006, John Paravantis wrote:
> BAD MOVE. I'd much rather have [lagged variables] readily apparent
> on the main screen. How about offering the user an OPTION?
I'm not ruling that out, but could you (or anyone) explain why you
want to see lags in the main screen?
With first differences, logs, or other transformations, the
transformed variables should (obviously) be shown, because you might
want to select them for graphing, summary statistics, or whatever.
With lags, on the other hand, I can't see any use for them other
than as regressors (and they are visible OK in the dialog where you
choose regressors). Suppose you have a monthly dataset with several
variables, of which you want to have available 12 lags apiece for
regression purposes. Showing dozens of such variables in the main
window, it seems to me, is just filling the window with trash,
making it harder to find variables you might actually want to
examine individually.
Am I missing something here?
I agree with Allin. Actually, I'd go even further. If it were for me, I'd
even hide lags from the selection window you get when you estimate with
OLS, IV, VARs etc. (provided of course there's some way to include lags
in regressions interactively), because you have exacly the same problem,
possibly worse as the window is smaller.
Having used Linux exclusively for several years now, I have dim memories
of the way PcGive works, but I recall you have a very convenient way to
include a variable AND OPTIONALLY SOME LAGS in a regression interactively.
Lags get generated on the fly and discarded subsequently. This, by the
way, is a much saner way to go: imagine I
1) define a variable z
2) generate n lags: now I have z_1, ..., z_n
3) change z
now you have the potential for something very misleading, cause z(-1) is
different from z_1.
Riccardo `Jack' Lucchetti
Dipartimento di Economia
Università Politecnica delle Marche
jack(a)dea.unian.it
http://www.econ.univpm.it/lucchetti