8:30 a.m.
Hi all,
for some function I need to check whether the passed series corresponds
to the variable defining the cross-sectional dimension of a panel
dataset. Here is some pseudo-code:
<pseudocode>
function void foo (series G)
if $datatype == 3 && G==is_crossdim_index_series(G)
--> Run pexpand()
else
--> Some other way to construct the return series
endif
end function
I was thinking of a function like is_crossdim_index_series() which
returns a boolean.
An alternative way I was thinking about is running:
<values($obsminor) == values(G)>
However, there is not guarantee that this works correctly as it may be
just luck that (conditional on the active sample) the distinct values of
G just coincide with the ones of $obsminor I guess.
Of course, the equivalent function for the time-dimension may be
is_timedim_index_series()
Do you some other ideas?
Thanks,
Artur
8:59 a.m.
On Sun, 8 Sep 2019, Artur Tarassow wrote:
Hi all,
for some function I need to check whether the passed series corresponds to
the variable defining the cross-sectional dimension of a panel dataset.
[...]
Do you some other ideas?
If the variable in question is guaranteed to be discrete, you could use
this:
<hansl>
function scalar is_crossdim_index_series(series x)
ret = isdiscrete(x)
if !ret
return ret
endif
matrix H = mxtab(x, $unit) .> 0
# check for 1-to-1 correspondence
chk = sumr(H) | sumc(H)'
ret = (maxc(chk) == 1) && (minc(chk) == 1)
return ret
end function
# example
open abdata.gdt --quiet
eval is_crossdim_index_series(YEAR)
discrete unit
eval is_crossdim_index_series(unit)
</hansl>
-------------------------------------------------------
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
-------------------------------------------------------
7:15 p.m.
Am 08.09.19 um 10:59 schrieb Riccardo (Jack) Lucchetti:
On Sun, 8 Sep 2019, Artur Tarassow wrote:
> Hi all,
>
> for some function I need to check whether the passed series
> corresponds to the variable defining the cross-sectional dimension of
> a panel dataset.
[...]
> Do you some other ideas?
If the variable in question is guaranteed to be discrete, you could
use this:
<hansl>
function scalar is_crossdim_index_series(series x)
ret = isdiscrete(x)
if !ret
return ret
endif
matrix H = mxtab(x, $unit) .> 0
# check for 1-to-1 correspondence
chk = sumr(H) | sumc(H)'
ret = (maxc(chk) == 1) && (minc(chk) == 1)
return ret
end function
# example
open abdata.gdt --quiet
eval is_crossdim_index_series(YEAR)
discrete unit
eval is_crossdim_index_series(unit)
</hansl>
Nice solution, Jack. Works fine here. Maybe another candidate for
extra.gfn? Looks like a basic helper function to me.
Best,
Artur
8:25 p.m.
On Mon, 9 Sep 2019, Artur Tarassow wrote:
Am 08.09.19 um 10:59 schrieb Riccardo (Jack) Lucchetti:
> On Sun, 8 Sep 2019, Artur Tarassow wrote:
>
>> Hi all,
>>
>> for some function I need to check whether the passed series corresponds to
>> the variable defining the cross-sectional dimension of a panel dataset.
>
> [...]
>
>> Do you some other ideas?
>
> If the variable in question is guaranteed to be discrete, you could use
> this:
>
> <hansl>
> function scalar is_crossdim_index_series(series x)
> ret = isdiscrete(x)
> if !ret
> return ret
> endif
>
> matrix H = mxtab(x, $unit) .> 0
> # check for 1-to-1 correspondence
> chk = sumr(H) | sumc(H)'
> ret = (maxc(chk) == 1) && (minc(chk) == 1)
> return ret
> end function
>
> # example
>
> open abdata.gdt --quiet
> eval is_crossdim_index_series(YEAR)
> discrete unit
> eval is_crossdim_index_series(unit)
> </hansl>
Nice solution, Jack. Works fine here. Maybe another candidate for extra.gfn?
Looks like a basic helper function to me.
Sorry, I haven't been following this very closely, but might it work
just to check whether the putative "crossdim_index_series" has
correlation 1.0 with $unit? And similarly for the built-in "time" if
you want to check for a putative panel-time variable.
Moreover (but here I have to stress the caveat above more firmly)
why would one need this when you have $unit and time?
Allin
9:22 p.m.
On Mon, 9 Sep 2019, Allin Cottrell wrote:
Sorry, I haven't been following this very closely, but might it
work just to
check whether the putative "crossdim_index_series" has correlation 1.0 with
$unit? And similarly for the built-in "time" if you want to check for a
putative panel-time variable.
Whell, not necessarily. It may happen that the unit identifier variable
doesn't have regular increments. Example:
<hansl>
nulldata 9
series tim = {1;2;3;1;2;3;1;2;3}
series id = {1;1;1;2;2;2;101;101;101}
setobs id tim --panel-vars
eval corr($unit, id)
</hansl>
-------------------------------------------------------
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
-------------------------------------------------------
10:19 p.m.
On Mon, 9 Sep 2019, Riccardo (Jack) Lucchetti wrote:
On Mon, 9 Sep 2019, Allin Cottrell wrote:
> Sorry, I haven't been following this very closely, but might it work just
> to check whether the putative "crossdim_index_series" has correlation 1.0
> with $unit? And similarly for the built-in "time" if you want to check for
> a putative panel-time variable.
Whell, not necessarily. It may happen that the unit identifier variable
doesn't have regular increments. Example:
<hansl>
nulldata 9
series tim = {1;2;3;1;2;3;1;2;3}
series id = {1;1;1;2;2;2;101;101;101}
setobs id tim --panel-vars
eval corr($unit, id)
</hansl>
Granted, my thought was wrong. But backing up a step (and sorry if
I've just missed the point) why would one need to test a series such
as "id" if one has $unit available? ("Read <URL>" might
suffice!)
Allin
1685
days inactive
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days old
5 comments
3 participants
participants (3)
-
Allin Cottrell -
Artur Tarassow -
Riccardo (Jack) Lucchetti