st: Too small standard errors with QREG?

["Jeannette Wicks-Lim" <janetlim@econs.umass.edu>]

Hi,
I've estimated a quantile regression (QREG) which requires an iterative 
process to minimize the sum of the absolute residuals. Something strange 
happens with my results: the standard errors are extremly small (note that 
the CI are points rather than ranges...). Does anyone have any thoughts 
about why this might be happening? My model does have in it many variables 
(lots of interaction terms) but I don't hink that should be a problem given 
the large sample size.

Thanks in advance for any help!

Below I've pasted some of the output:

.9 Quantile regression                               Number of obs = 
422027
 Raw sum of deviations 66889.66 (about 2.5118887)
 Min sum of deviations  64818.5                     Pseudo R2     = 
0.0310

------------------------------------------------------------------------------
    lnrwage |      Coef.   Std. Err.      t    P>|t|     [95% Conf. 
Interval]
-------------+----------------------------------------------------------------
   lnpmin1r |   .1971322   1.53e-15        .   0.000     .1971322 
.1971322
  _Iyear_78 |   -.004403   3.95e-16        . 
.000     -.004403    -.004403
  _Iyear_79 |   .0034332   4.48e-16        .   0.000     .0034332 
.0034332
  _Iyear_80 |  -.0193586   5.30e-16        . 
0.000    -.0193586   -.0193586
  _Iyear_81 |   .0143617   3.49e-16        .   0.000     .0143617 
.0143617
  _Iyear_83 |   .0150885   3.69e-16        .   0.000     .0150885 
.0150885
  _Iyear_84 |   .0203746   4.08e-16        .   0.000     .0203746 
.0203746
  _Iyear_85 |   .0300213   4.44e-16        .   0.000     .0300213 
.0300213
  _Iyear_86 |   .0464875   4.63e-16        .   0.000     .0464875 
.0464875
  _Iyear_87 |   .0385665   5.01e-16        .   0.000     .0385665 
.0385665
  _Iyear_88 |   .0299613   5.33e-16        .   0.000     .0299613 
.0299613
  _Iyear_89 |   .0426883   5.65e-16        .   0.000     .0426883 
.0426883
  _Iyear_90 |   .0202615   5.32e-16        .   0.000     .0202615 
.0202615
  _Iyear_91 |    .000379   4.67e-16        .   0.000      .000379 
.000379
  _Iyear_92 |    .000173   4.68e-16        .   0.000      .000173 
.000173
  _Iyear_93 |     .00088   5.00e-16        .   0.000       .00088 
.00088


Jeannette Wicks-Lim
Department of Economics
University of Massachusetts, Amherst
(413) 577-0820 
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