It looks like your data is balanced but that on some variables you have
lots of missing data. There are two solutions: 1) don't use the
variables with missing data 2) do some form of imputation as I
suggested earlier.
-- Maarten
--- "Jessica [iso-8859-1] �lschl�ger" <[email protected]>
wrote:
> Dear Maarten,
>
>
> when I'm typing xtdescribe for my dataset I get the following output:
>
>
> . xtdescribe
>
> coid: 1, 2, ..., 30 n =
> 30
> year: 1950, 1951, ..., 2005 T =
> 56
> Delta(year) = 1 unit
> Span(year) = 56 periods
> (coid*year uniquely identifies each observation)
>
> Distribution of T_i: min 5% 25% 50% 75%
> 95% max
> 56 56 56 56 56
> 56 56
>
> Freq. Percent Cum. | Pattern
>
>
------------------------+----------------------------------------------------------
> 30 100.00 100.00 |
> 11111111111111111111111111111111111111111111111111111
>
>
---------------------------+----------------------------------------------------------
> 30 100.00
> |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX
>
> Does this tell you something I haven't recognized yet?
>
> I also typed "sum if year >=1990" because this is the time span
> (1990-2005)for
> which I'm doing my regressions at the moment. The least numbers of
> observations
> for a single variable that stata returns is 85 (see below).
>
> Do you have any suggestions?
>
> Jessica
>
>
> . sum if year >=1990
>
> Variable | Obs Mean Std. Dev. Min
> Max
>
-------------+--------------------------------------------------------
> coid | 480 15.5 8.664472 1
> 30
> eu_15 | 480 .5 .5005216 0
> 1
> year | 480 1997.5 4.614582 1990
> 2005
> corprate | 366 33.99372 5.663233 16
> 50
> persrate | 268 44.28313 9.637002 13
> 68
>
-------------+--------------------------------------------------------
> vatrate | 436 17.50532 5.693931 3
> 25
> pitr | 85 17.00588 9.002372 4.6
> 41
> cetr | 204 26.71569 7.652872 10
> 43.7
> ketg | 204 22.23529 5.554781 11.1
> 37.4
> nwlc | 204 23.36667 8.837636 4.1
> 41
>
-------------+--------------------------------------------------------
> hbs | 474 -.4729114 6.205395 -63.96
> 16.16
> fdiout | 450 15767.68 33245.51 -11067
> 252012
> fdiin | 450 12668.6 30055.53 -38581
> 321274
> fdioutp | 450 124818.3 261967.7 0
> 2069013
> fdiinp | 450 96719.37 196991.8 0
> 1553955
>
-------------+--------------------------------------------------------
> gdp1955_2005 | 480 34067.26 127258.6 .39306
> 806621.9
> toexp | 245 2.93e+11 2.24e+12 1.08e+07
> 2.95e+13
> toexpppp | 245 1.58e+12 7.82e+12 1.10e+07
> 6.19e+13
> lbs | 433 -6.227229 75.19171 -791.5
> 172.16
> cpiti | 320 7.017344 2.086486 2.66
> 10
>
-------------+--------------------------------------------------------
> totrev | 463 481001.3 940469.4 78.7146
> 8091442
> totaltaxgdp | 463 35.67134 7.816183 16.57135
> 53.38145
> t1000gdp | 462 12.81689 5.196823 4.047751
> 30.31366
> t1100gdp | 462 9.469915 4.958679 0
> 26.37211
> t1200gdp | 462 2.974308 1.556358 0
> 12.81173
>
-------------+--------------------------------------------------------
> t2000gdp | 462 9.03067 5.152212 0
> 18.86867
> t3000gdp | 446 .3676013 .7287513 0
> 5.821948
> t4000gdp | 462 1.88998 1.048129 0
> 8.41538
> t5000gdp | 462 11.20277 2.966812 3.970961
> 17.90243
> t5111gdp | 462 6.187076 3.719843 0
> 62.55744
>
-------------+--------------------------------------------------------
> t5112gdp | 462 .2805195 .8740527 0
> 8.396804
> t5120gdp | 462 3.954499 1.534671 0
> 9.740898
> t6000gdp | 462 .1375409 .3561737 0
> 2.448328
> dirtgdp | 462 24.09241 6.522121 7.083571
> 40.22071
> indirtgdp | 462 11.20277 2.966812 3.970961
> 17.90243
>
-------------+--------------------------------------------------------
> (shortened)
>
> Zitat von Maarten buis <[email protected]>:
>
> > --- Maarten Buis asked:
> > > Are you using -xtreg- with the -fe- option to estimate your fixed
> > > effects model?
> >
> > --- Jessica Oelschlaeger wrote:
> > > Yes, I do.
> >
> > Than I am confused, -xtreg- with -fe- does not require balanced
> data,
> > so you should not loose that many units. See the example below:
> >
> > *--------------- begin example -------------
> > webuse nlswork, clear
> > xtdescribe
> > xtreg ln_w union south ttl_exp age , fe
> > *----------------- end example -------------
> >
> > -- Maarten
> >
> > -----------------------------------------
> > Maarten L. Buis
> > Department of Social Research Methodology
> > Vrije Universiteit Amsterdam
> > Boelelaan 1081
> > 1081 HV Amsterdam
> > The Netherlands
> >
> > visiting address:
> > Buitenveldertselaan 3 (Metropolitan), room Z434
> >
> > +31 20 5986715
> >
> > http://home.fsw.vu.nl/m.buis/
> > -----------------------------------------
> >
> >
> > __________________________________________________________
> > Sent from Yahoo! Mail - a smarter inbox http://uk.mail.yahoo.com
> >
> > *
> > * For searches and help try:
> > * http://www.stata.com/support/faqs/res/findit.html
> > * http://www.stata.com/support/statalist/faq
> > * http://www.ats.ucla.edu/stat/stata/
> >
>
>
> --
> Dipl. oec. Jessica �lschl�ger
>
> Forschungsstelle Europ�ische Integration
> Universtit�t Hohenheim
>
> mailto:[email protected]
>
>
> *
> * For searches and help try:
> * http://www.stata.com/support/faqs/res/findit.html
> * http://www.stata.com/support/statalist/faq
> * http://www.ats.ucla.edu/stat/stata/
>
-----------------------------------------
Maarten L. Buis
Department of Social Research Methodology
Vrije Universiteit Amsterdam
Boelelaan 1081
1081 HV Amsterdam
The Netherlands
visiting address:
Buitenveldertselaan 3 (Metropolitan), room Z434
+31 20 5986715
http://home.fsw.vu.nl/m.buis/
-----------------------------------------
__________________________________________________________
Sent from Yahoo! Mail - a smarter inbox http://uk.mail.yahoo.com
*
* For searches and help try:
* http://www.stata.com/support/faqs/res/findit.html
* http://www.stata.com/support/statalist/faq
* http://www.ats.ucla.edu/stat/stata/
