# st: xtreg & reg

 From "Lee Chuntao" To Subject st: xtreg & reg Date Wed, 20 Nov 2002 14:20:41 +0800

```Hi, Listers

I have a panel dataset. My problem is the xtreg and reg give out the
same result, can you tell me why?

. xtreg invest l_tobinq so1_q so2_q cash so1_cf so2_cf  nta

Random-effects GLS regression                   Number of obs      = 1680
Group variable (i) : i                          Number of groups   = 280

R-sq:  within  = 0.1172                         Obs per group: min = 6
between = 0.5438                                        avg = 6.0
overall = 0.1890                                        max = 6

Random effects u_i ~ Gaussian                   Wald chi2(7)       = 389.67
corr(u_i, X)       = 0 (assumed)                Prob > chi2        = 0.0000

invest       Coef.   Std. Err.      z    P>z     [95% Conf. Interval]

l_tobinq    .1158289   .0633886     1.83   0.068    -.0084104 .2400682
so1_q     -.0308517   .0497988    -0.62   0.536    -.1284555 .0667521
so2_q     -.0413252   .0666455    -0.62   0.535     -.171948 .0892976
cash        .1281167    .008567    14.95   0.000     .1113257 .1449078
so1_cf    .2623394    .0345842     7.59   0.000     .1945556 .3301232
so2_cf    .15333        .1796647     0.85   0.393    -.1988064 .5054664
nta         -.1325352    .070429     -1.88   0.060    -.2705735 .0055031
_cons    3.003068    1.49794        2.00   0.045     .0671603 5.938975

sigma_u           0
sigma_e   2.5762731
rho           0   (fraction of variance due to u_i)

. reg invest l_tobinq so1_q so2_q cash so1_cf so2_cf  nta

Source        SS       df       MS              Number of obs =    1680
F(  7,  1672) =   55.67
Model   2449.83361     7   349.97623           Prob > F =  0.0000
Residual   10511.6469  1672  6.28687016           R-squared =  0.1890
Total   12961.4805  1679  7.71976207           Root MSE =  2.5074

invest       Coef.   Std. Err.      t    P>t     [95% Conf. Interval]

l_tobinq    .1158289    .0633886     1.83   0.068    -.0085004 .2401582
so1_q      -.0308517   .0497988    -0.62   0.536    -.1285262 .0668228
so2_q      -.0413252   .0666455    -0.62   0.535    -.1720426 .0893922
cash         .1281167    .008567    14.95   0.000     .1113135 .14492
so1_cf      .2623394    .0345842    7.59   0.000     .1945065 .3301723
so2_cf      .15333        .1796647    0.85   0.394    -.1990615 .5057214
nta           -.1325352    .070429    -1.88    0.060    -.2706735 .0056031
_cons      3.003068    1.49794      2.00     0.045     .0650335 5.941102

.

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```