用xtreg命令,得到如下结果:
Fixed-effects (within) regression Number of obs = 245
Group variable: v2 Number of groups = 35
R-sq: within = 0.6662 Obs per group: min = 7
between = 0.8320 avg = 7.0
overall = 0.7800 max = 7
F(7,203) = 57.87
corr(u_i, Xb) = 0.6659 Prob > F = 0.0000
------------------------------------------------------------------------------
urbanscale | Coef. Std. Err. t P>|t| [95% Conf. Interval]
-------------+----------------------------------------------------------------
pop | .1699761 .0556392 3.05 0.003 .0602713 .2796809
zzrk | .1585806 .0513219 3.09 0.002 .0573881 .259773
incomeper | .0038924 .0010555 3.69 0.000 .0018113 .0059736
landprice | .003809 .0084058 0.45 0.651 -.0127648 .0203827
hprice | .0221776 .0030435 7.29 0.000 .0161767 .0281784
acce2 | .0008565 .0005598 1.53 0.128 -.0002473 .0019604
roadper | 4.85866 1.160331 4.19 0.000 2.570813 7.146506
用areg命令得到如下结果:
Linear regression, absorbing indicators Number of obs = 245 F( 7, 203) = 57.87 Prob > F = 0.0000 R-squared = 0.9757 Adj R-squared = 0.9707 Root MSE = 41.603
------------------------------------------------------------------------------ urbanscale | Coef. Std. Err. t P>|t| [95% Conf. Interval]-------------+---------------------------------------------------------------- pop | .1699761 .0556392 3.05 0.003 .0602713 .2796809 zzrk | .1585806 .0513219 3.09 0.002 .0573881 .259773 incomeper | .0038924 .0010555 3.69 0.000 .0018113 .0059736 landprice | .003809 .0084058 0.45 0.651 -.0127648 .0203827 total | .0008565 .0005598 1.53 0.128 -.0002473 .0019604 roadper | 4.85866 1.160331 4.19 0.000 2.570813 7.146506 hprice | .0221776 .0030435 7.29 0.000 .0161767 .0281784 _cons | 34.12666 22.66248 1.51 0.134 -10.55738 78.81069-------------+---------------------------------------------------------------- city | F(34, 203) = 26.226 0.000 (35 categories)
请问:应该用 R-squared呢?为什么会出现如此不同的结果?谢谢!