Re: [Gretl-users] Computing an index for unique combinations of discrete variables

I don't see your point... In your case ndigits is 0 and therefore: unique = region * 10 + sector This is enough to produce unique values for each region/sector combination. (1,2) and (2,1) must be treated as different and they do... On Thu, 2013-11-21 at 15:57 +0100, Pindar wrote: > Yes, nice, but one has to check that 'region' and 'sector' do not > share a common cluster ID like in > > <hansl> > region = randgen(i,1,10) > sector = randgen(i,1,5) > <hansl> > > Since combinations like (1,2) and (2,1) are treated as being > different. > Hence, with a primary data manipulation 'sector = randgen(i,1,5) +100' > things should be fine. > > 21.11.2013 15:13, Riccardo (Jack) Lucchetti: > >> On Thu, 21 Nov 2013, Giuseppe Vittucci wrote: >> >>> Hi, >>> >>> I have firm level data and two categorical variables (region and >>> sector). >>> I need to define another variable which is an index identifying >>> the >>> unique combinations region-sector each firm belongs to, so I can >>> use it >>> in computing cluster-robust s.e. >>> >>> One way to do this is to use the command "values" for region and >>> sector >>> and then use a nested loop, but this seems quite >>> time-consuming... >>> >>> Is there a simpler way in gretl to do it? >> You mean, like this? >> >> <hansl> >> nulldata 1024 >> >> # simulated data >> region = randgen(i,1,20) >> sector = randgen(i,10,99) >> # ---------------------------------------------- >> scalar ndigits = floor(log10(max(sector))) >> series unique = region * 10^(ndigits+1) + sector >> </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 >> ------------------------------------------------------- >> >> >> _______________________________________________ >> Gretl-users mailing list >> Gretl-users(a)lists.wfu.edu >> http://lists.wfu.edu/mailman/listinfo/gretl-users > _______________________________________________ > Gretl-users mailing list > Gretl-users(a)lists.wfu.edu > http://lists.wfu.edu/mailman/listinfo/gretl-users _______________________________________________ Gretl-users mailing list Gretl-users(a)lists.wfu.edu http://lists.wfu.edu/mailman/listinfo/gretl-users