Re: st: Strange -xi- behavior when naming new variables

[Nick Cox <njcoxstata@gmail.com>]

Whatever happened, my guess is that it is more likely to be a
side-effect of trying to do exact arithmetic with multiples of .05,
which will not work on a binary machine.

See, most recently,

<http://www.hsph.harvard.edu/cgi-bin/lwgate/STATALIST/archives/statalist.1105/date/article-609.html>

and beyond that

SJ-10-1 pr0051  . . . . . . . . . . . . Stata tip 85: Looping over nonintegers
        . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  N. J. Cox
        Q1/10   SJ 10(1):160--163                                (no commands)
        tip on using forvalues to loop over numbers

Try loops over 5(5)95 or 80(5)95. To format leading zeros

forval j = 5(5)95 {
      local J : di %02.0f `j'
     <work with `J'>
}

Nick

2011/5/18 Jorge Eduardo Pérez Pérez <perez.jorge@ur.edu.co>:

> I have been getting strange results using -xi- in conjuction with -qreg-
>
> I ran the following code to get some quantile regression estimates:
>
> glo cont "personas_hogar edad edadsq"
> glo cat "trabajo_permanente ocupacion actividad_empresa
> tipo_trabajador sexo ultimo_grado_estudios"
> glo ccat ""
> foreach x in $cat {
>        glo ccat "$ccat i.`x'"
> }
> forv x=0.05(0.05)0.9501 {
>        xi: qreg lsalario_real_mes treatment i.area2 i.trimestre $cont $ccat
> [fw=fex], nolog quantile(`x')
>        est save "cqte_c_fex_nob_`x'.ster", replace
> }
>
> The regression for quantile 0.75 did not converge and the loop ended
> with a break, so I skipped that quantile, and reran the last loop
> starting at the 0.8 quantile, i.e.
>
> forv x=0.8(0.05)0.9501 { ....
>
> At this point, -xi- changed the convention for naming the variables.
> Since I saved the estimates, I got the command that was issued
> everytime by typing:
>
> glo a: dir . files "cqte_c_fex_nob_*"
> foreach x in $a {
>        est use `x'
>        di "`x' ***********************************"
>        di ""
>        di e(cmdline)
>        di ""
> }
>
> And got:
>
> cqte_c_fex_nob_.7000000000000001.ster ***********************************
>
> qreg lsalario_real_mes treatment _Iarea2_* _Itrimestre_*
> personas_hogar edad edadsq  _Itrabajo_p_* _Iocupacion_* _
>> Iactividad_* _Itipo_trab_* _Isexo_* _Iultimo_gr_* [fw=fex], nolog quantile(.7000000000000001)
>
> cqte_c_fex_nob_.8.ster ***********************************
>
> qreg lsalario_real_mes treatment _Iarea2_* _Itrimestre_*
> personas_hogar edad edadsq  _Itrabajo_p_* _Iocupaciona* _
>> Iactividad_* _Itipo_trab_* _Isexo_* _Iultimo_gr_* [fw=fex], nolog quantile(.8)
>
> Notice the difference between the two commands: _Iocupacion_* and
> _Iocupaciona*_ !!!!
>
> Is this something related to some variables left behind by -xi- when
> the break occurred? Could this be a bug?
>

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