GMM-function in dpanel
by Sven Schreiber
Hi,
trying to use dpanel "seriously", I discovered that apparently the GMM()
function for specifying predetermined variables does not accept list
arguments, which makes dpanel specifications quite verbose and difficult
to adjust. So it would be nice and seem natural if named lists could be
accepted.
Also, I got an error when there was (accidentally) a blank between the
number argument and the comma, like so:
GMM(myvariable, 1 , 2)
IMHO that looks like a bug (in the parser?).
thanks,
sven
10 years, 3 months
memory with many discrete variables in large (panel) dataset
by Sven Schreiber
Hi,
I'd like to raise an issue which is probably quite fundamental in terms
of data handling. I'm currently working on a large panel dataset,
meaning that gretl occupies more than 600MB of memory with the data
loaded. In terms of file sizes, the Stata file version occupies 42MB,
the gretl workfile only about 3.5MB. This shows that gretl stores the
data very efficiently (by zipping), but OTOH opening and saving takes
quite some time. Actually it is much faster even in gretl to import the
Stata file instead of the native gretl file.
Now I can admit beforehand that I do not actually need most of the
variables in there and I can work with a stripped-down version.
(However, as a side remark: this is complicated by the fact that I could
not delete the unwanted variables in a loop, and when deleting manually
I often got the error "too many items selected".)
Nevertheless, given the fact that many of the variables in there are
discrete integer-valued which could be saved as a signed single byte,
and that (I think) I know that gretl stores every variable as
double-precision 8-byte numbers, there are huge potential memory savings
and speed improvements. Maybe that's something to think about for the
longer term.
Or are there alternatives that I have missed?
thanks,
sven
10 years, 3 months
Duplicate variable name in workfile
by Sven Schreiber
Hi,
I stumbled across a very strange thing, namely ending up with two
variables with the same name "nordwest" in a panel workfile. I'm
attaching a stripped-down version in the hope that the effect is still
visible when the file gets to you.
The source was a Stata file, but I just re-imported to check, and only
one "nordwest" appears right after the import. So it must have been
something after that, within gretl. BTW, the content of the variables
were not identical, which is of course even worse.
This is with the 32bit gretl 1.9.14 on Win7.
Thanks,
sven
10 years, 3 months