Hello,

I have run the following regression:
Code:
. logit change firmsize profitability leverage age capitalintensity CAPEX KZindex elektricityge
> nerator Carbonleakage i.twodigitsNACE WestFlanders Hainaut Antwerp Brussels FlemishBrabant Li
> mbourg Liege Namur WalloonBrabant Luxembourg SME publicfirm

note: 16.twodigitsNACE != 0 predicts success perfectly
      16.twodigitsNACE dropped and 2 obs not used

note: 21.twodigitsNACE != 0 predicts success perfectly
      21.twodigitsNACE dropped and 3 obs not used

note: 25.twodigitsNACE != 0 predicts success perfectly
      25.twodigitsNACE dropped and 2 obs not used

note: 28.twodigitsNACE != 0 predicts success perfectly
      28.twodigitsNACE dropped and 1 obs not used

note: 30.twodigitsNACE != 0 predicts success perfectly
      30.twodigitsNACE dropped and 1 obs not used

note: 42.twodigitsNACE != 0 predicts success perfectly
      42.twodigitsNACE dropped and 5 obs not used

note: 47.twodigitsNACE != 0 predicts failure perfectly
      47.twodigitsNACE dropped and 1 obs not used

note: 49.twodigitsNACE != 0 predicts success perfectly
      49.twodigitsNACE dropped and 2 obs not used

note: 61.twodigitsNACE != 0 predicts failure perfectly
      61.twodigitsNACE dropped and 1 obs not used

note: 63.twodigitsNACE != 0 predicts failure perfectly
      63.twodigitsNACE dropped and 2 obs not used

note: 70.twodigitsNACE != 0 predicts failure perfectly
      70.twodigitsNACE dropped and 1 obs not used

note: 72.twodigitsNACE != 0 predicts success perfectly
      72.twodigitsNACE dropped and 1 obs not used

note: 81.twodigitsNACE != 0 predicts success perfectly
      81.twodigitsNACE dropped and 1 obs not used

note: Namur != 0 predicts failure perfectly
      Namur dropped and 1 obs not used

Iteration 0:   log likelihood = -98.836643  
Iteration 1:   log likelihood = -79.803416  
Iteration 2:   log likelihood = -79.587861  
Iteration 3:   log likelihood = -79.566988  
Iteration 4:   log likelihood = -79.565487  
Iteration 5:   log likelihood = -79.565147  
Iteration 6:   log likelihood = -79.565092  
Iteration 7:   log likelihood = -79.565086  

Logistic regression                             Number of obs     =        143
                                                LR chi2(33)       =      38.54
                                                Prob > chi2       =     0.2331
Log likelihood = -79.565086                     Pseudo R2         =     0.1950

--------------------------------------------------------------------------------------
              change |      Coef.   Std. Err.      z    P>|z|     [95% Conf. Interval]
---------------------+----------------------------------------------------------------
            firmsize |   .5369456   .2847299     1.89   0.059    -.0211148    1.095006
       profitability |  -4.871327   6.538349    -0.75   0.456    -17.68626    7.943602
            leverage |  -2.234129   1.071087    -2.09   0.037    -4.333422   -.1348367
                 age |   .0072455   .0098076     0.74   0.460     -.011977     .026468
    capitalintensity |  -1.686705   1.344654    -1.25   0.210    -4.322178    .9487684
               CAPEX |   1.105687   3.453339     0.32   0.749    -5.662732    7.874106
             KZindex |   .2451881    .191563     1.28   0.201    -.1302685    .6206447
elektricitygenerator |    12.2858   954.6576     0.01   0.990    -1858.809     1883.38
       Carbonleakage |   -.625777   .5337667    -1.17   0.241     -1.67194    .4203865
                     |
       twodigitsNACE |
                 10  |  -.2720088   1.277316    -0.21   0.831    -2.775502    2.231484
                 11  |   2.094524   1.844136     1.14   0.256    -1.519916    5.708964
                 13  |   .2188543   1.574521     0.14   0.889     -2.86715    3.304859
                 16  |          0  (empty)
                 17  |  -.4607484   1.454024    -0.32   0.751    -3.310583    2.389086
                 19  |   .2352189   1.575869     0.15   0.881    -2.853428    3.323866
                 20  |   .2973133   1.232916     0.24   0.809    -2.119157    2.713784
                 21  |          0  (empty)
                 22  |  -.5714206   1.640488    -0.35   0.728    -3.786718    2.643877
                 23  |   1.222801   1.213726     1.01   0.314    -1.156058     3.60166
                 24  |   .8195506   1.376575     0.60   0.552    -1.878486    3.517587
                 25  |          0  (empty)
                 28  |          0  (empty)
                 29  |   .0334485   2.098225     0.02   0.987    -4.078997    4.145894
                 30  |          0  (empty)
                 35  |  -12.92753   954.6579    -0.01   0.989    -1884.023    1858.168
                 42  |          0  (empty)
                 46  |    .638123   1.392489     0.46   0.647    -2.091105    3.367351
                 47  |          0  (empty)
                 49  |          0  (empty)
                 52  |   1.324916   1.898157     0.70   0.485    -2.395404    5.045236
                 61  |          0  (empty)
                 63  |          0  (empty)
                 70  |          0  (empty)
                 72  |          0  (empty)
                 81  |          0  (empty)
                     |
        WestFlanders |  -.0334296   .8350943    -0.04   0.968    -1.670184    1.603325
             Hainaut |  -1.990829    .889228    -2.24   0.025    -3.733684   -.2479741
             Antwerp |  -1.622771   .7301036    -2.22   0.026    -3.053747   -.1917937
            Brussels |   -2.43887    1.00253    -2.43   0.015    -4.403793   -.4739474
      FlemishBrabant |   .5337495   1.402777     0.38   0.704    -2.215643    3.283142
            Limbourg |  -.6921454    .814151    -0.85   0.395    -2.287852    .9035613
               Liege |  -1.329429    .944401    -1.41   0.159    -3.180421    .5215631
               Namur |          0  (omitted)
      WalloonBrabant |  -2.447982   1.389671    -1.76   0.078    -5.171687    .2757223
          Luxembourg |  -1.161801   1.423928    -0.82   0.415    -3.952649    1.629048
                 SME |   1.970419   .8058729     2.45   0.014     .3909376    3.549901
          publicfirm |   .1173165   1.683249     0.07   0.944     -3.18179    3.416423
               _cons |  -8.413368   5.586249    -1.51   0.132    -19.36221    2.535478
--------------------------------------------------------------------------------------
followed by a test for specification error

Code:
. linktest

Iteration 0:   log likelihood = -98.836643  
Iteration 1:   log likelihood = -80.115266  
Iteration 2:   log likelihood = -79.734377  
Iteration 3:   log likelihood = -79.150294  
Iteration 4:   log likelihood = -79.148124  
Iteration 5:   log likelihood = -79.148124  

Logistic regression                             Number of obs     =        143
                                                LR chi2(2)        =      39.38
                                                Prob > chi2       =     0.0000
Log likelihood = -79.148124                     Pseudo R2         =     0.1992

------------------------------------------------------------------------------
      change |      Coef.   Std. Err.      z    P>|z|     [95% Conf. Interval]
-------------+----------------------------------------------------------------
        _hat |   1.018599   .2037787     5.00   0.000     .6192005    1.417998
      _hatsq |  -.1179535    .129042    -0.91   0.361    -.3708711    .1349641
       _cons |   .1115148   .2294243     0.49   0.627    -.3381485    .5611782
------------------------------------------------------------------------------
Note: 1 failure and 0 successes completely determined.
Because this test does not indicate any specification errors, I do not make use of robust standard errors. Is it safer to use robust standard errors anyways, because the link test might not be performing well (as I have read in a previous post)? What I find striking is that when I use robust standard errors, my model is significant, while it was not in the previous one.

Code:
 logit change firmsize profitability leverage age capitalintensity CAPEX KZindex elektricityge
> nerator Carbonleakage i.twodigitsNACE WestFlanders Hainaut Antwerp Brussels FlemishBrabant Li
> mbourg Liege Namur WalloonBrabant Luxembourg SME publicfirm, vce(robust)

note: 16.twodigitsNACE != 0 predicts success perfectly
      16.twodigitsNACE dropped and 2 obs not used

note: 21.twodigitsNACE != 0 predicts success perfectly
      21.twodigitsNACE dropped and 3 obs not used

note: 25.twodigitsNACE != 0 predicts success perfectly
      25.twodigitsNACE dropped and 2 obs not used

note: 28.twodigitsNACE != 0 predicts success perfectly
      28.twodigitsNACE dropped and 1 obs not used

note: 30.twodigitsNACE != 0 predicts success perfectly
      30.twodigitsNACE dropped and 1 obs not used

note: 42.twodigitsNACE != 0 predicts success perfectly
      42.twodigitsNACE dropped and 5 obs not used

note: 47.twodigitsNACE != 0 predicts failure perfectly
      47.twodigitsNACE dropped and 1 obs not used

note: 49.twodigitsNACE != 0 predicts success perfectly
      49.twodigitsNACE dropped and 2 obs not used

note: 61.twodigitsNACE != 0 predicts failure perfectly
      61.twodigitsNACE dropped and 1 obs not used

note: 63.twodigitsNACE != 0 predicts failure perfectly
      63.twodigitsNACE dropped and 2 obs not used

note: 70.twodigitsNACE != 0 predicts failure perfectly
      70.twodigitsNACE dropped and 1 obs not used

note: 72.twodigitsNACE != 0 predicts success perfectly
      72.twodigitsNACE dropped and 1 obs not used

note: 81.twodigitsNACE != 0 predicts success perfectly
      81.twodigitsNACE dropped and 1 obs not used

note: Namur != 0 predicts failure perfectly
      Namur dropped and 1 obs not used

Iteration 0:   log pseudolikelihood = -98.836643  
Iteration 1:   log pseudolikelihood = -79.803416  
Iteration 2:   log pseudolikelihood = -79.587861  
Iteration 3:   log pseudolikelihood = -79.566988  
Iteration 4:   log pseudolikelihood = -79.565487  
Iteration 5:   log pseudolikelihood = -79.565147  
Iteration 6:   log pseudolikelihood = -79.565092  
Iteration 7:   log pseudolikelihood = -79.565086  

Logistic regression                             Number of obs     =        143
                                                Wald chi2(33)     =     210.53
                                                Prob > chi2       =     0.0000
Log pseudolikelihood = -79.565086               Pseudo R2         =     0.1950

--------------------------------------------------------------------------------------
                     |               Robust
              change |      Coef.   Std. Err.      z    P>|z|     [95% Conf. Interval]
---------------------+----------------------------------------------------------------
            firmsize |   .5369456   .2694897     1.99   0.046     .0087555    1.065136
       profitability |  -4.871327   6.919936    -0.70   0.481    -18.43415    8.691497
            leverage |  -2.234129   .9677091    -2.31   0.021    -4.130804   -.3374542
                 age |   .0072455   .0099999     0.72   0.469    -.0123539    .0268449
    capitalintensity |  -1.686705   1.266685    -1.33   0.183    -4.169363    .7959533
               CAPEX |   1.105687   3.557574     0.31   0.756    -5.867029    8.078404
             KZindex |   .2451881    .164491     1.49   0.136    -.0772083    .5675845
elektricitygenerator |    12.2858   2.103114     5.84   0.000     8.163768    16.40782
       Carbonleakage |   -.625777   .5255647    -1.19   0.234    -1.655865    .4043108
                     |
       twodigitsNACE |
                 10  |  -.2720088   1.375848    -0.20   0.843    -2.968622    2.424604
                 11  |   2.094524   1.867219     1.12   0.262    -1.565159    5.754207
                 13  |   .2188543   1.611141     0.14   0.892    -2.938923    3.376632
                 16  |          0  (empty)
                 17  |  -.4607484   1.592633    -0.29   0.772    -3.582253    2.660756
                 19  |   .2352189   1.617443     0.15   0.884    -2.934911    3.405349
                 20  |   .2973133   1.314841     0.23   0.821    -2.279728    2.874354
                 21  |          0  (empty)
                 22  |  -.5714206     1.6593    -0.34   0.731    -3.823588    2.680747
                 23  |   1.222801   1.255445     0.97   0.330    -1.237825    3.683427
                 24  |   .8195506   1.395696     0.59   0.557    -1.915963    3.555064
                 25  |          0  (empty)
                 28  |          0  (empty)
                 29  |   .0334485   1.657259     0.02   0.984    -3.214719    3.281616
                 30  |          0  (empty)
                 35  |  -12.92753   2.057606    -6.28   0.000    -16.96036   -8.894691
                 42  |          0  (empty)
                 46  |    .638123   1.400915     0.46   0.649    -2.107621    3.383867
                 47  |          0  (empty)
                 49  |          0  (empty)
                 52  |   1.324916   1.606922     0.82   0.410    -1.824592    4.474425
                 61  |          0  (empty)
                 63  |          0  (empty)
                 70  |          0  (empty)
                 72  |          0  (empty)
                 81  |          0  (empty)
                     |
        WestFlanders |  -.0334296   .8781885    -0.04   0.970    -1.754647    1.687788
             Hainaut |  -1.990829   .7991805    -2.49   0.013    -3.557194    -.424464
             Antwerp |  -1.622771   .6982627    -2.32   0.020     -2.99134   -.2542008
            Brussels |   -2.43887   .8798601    -2.77   0.006    -4.163364   -.7143759
      FlemishBrabant |   .5337495   1.117561     0.48   0.633    -1.656631    2.724129
            Limbourg |  -.6921454   .8206851    -0.84   0.399    -2.300659    .9163678
               Liege |  -1.329429   1.024602    -1.30   0.194    -3.337612     .678754
               Namur |          0  (omitted)
      WalloonBrabant |  -2.447982   1.391213    -1.76   0.078    -5.174709    .2787442
          Luxembourg |  -1.161801    1.30263    -0.89   0.372    -3.714908    1.391307
                 SME |   1.970419   .7692936     2.56   0.010     .4626317    3.478207
          publicfirm |   .1173165   2.651193     0.04   0.965    -5.078926    5.313559
               _cons |  -8.413368   5.235232    -1.61   0.108    -18.67423    1.847498
--------------------------------------------------------------------------------------

.




Kind regards,
Timea De Wispelaere