STATA空间计量help 命令中对SAR(SLM) 和SAC(也即SEM)模型定义如下: - Spatial Lag Model: Y = BX + rWy + e ; e = lWe+u
- Spatial Error Model: Y = BX + e ; e = lWe+u
- Spatial Durbin Model: Y = BX + aWX* + rWy + e ; e = lWe+u
- General Spatial Model: Y = BX + rWy + LW1y + e ; e = lW1e+u
SAR模型 举例命令和报告结果如下,提问:请问“Rho”和sigma是指什么?是不是模型中的r?
. sysuse spregsar.dta, clear
. spregsar y x1 x2 , wmfile(SPWcs) mfx(lin) test
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y | Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------+----------------------------------------------------------------
y |
x1 | -.252788 .1007052 -2.51 0.012 -.4501667 -.0554094
x2 | -1.585978 .3198759 -4.96 0.000 -2.212924 -.959033
_cons | 64.04514 6.233457 10.27 0.000 51.82779 76.26249
-------------+----------------------------------------------------------------
Rho | .0211161 .0197638 1.07 0.285 -.0176202 .0598524
Sigma | 10.94111 1.10546 9.90 0.000 8.774445 13.10777
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LR Test SAR vs. OLS (Rho=0): 1.1415 P-Value > Chi2(1) 0.2853
Acceptable Range for Rho: -0.3199 < Rho < 0.1633
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SAC模型 举例命令和报告结果如下,提问:请问“Rho”、lambda、sigma是指什么?
sysuse spregsac.dta, clear
. spregsac y x1 x2 , wmfile(SPWcs) mfx(lin) test
| Coef. Std. Err. z P>|z| [95% Conf. Interval]
-------------+----------------------------------------------------------------
y |
x1 | -.2641515 .0976133 -2.71 0.007 -.4554701 -.072833
x2 | -1.501453 .3136039 -4.79 0.000 -2.116105 -.8868004
_cons | 63.46502 6.002194 10.57 0.000 51.70094 75.2291
-------------+----------------------------------------------------------------
Rho | .0596863 .0318249 1.88 0.061 -.0026895 .122062
Lambda | -.0335656 .0281033 -1.19 0.232 -.0886471 .0215159
Sigma | 10.6488 1.08717 9.79 0.000 8.517984 12.77961
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LR Test (Rho=0): 3.5173 P-Value > Chi2(1) 0.0607
LR Test (Lambda=0): 1.4265 P-Value > Chi2(1) 0.2323
LR Test SAC vs. OLS (Rho+Lambda=0): 4.2439 P-Value > Chi2(2) 0.1198
Acceptable Range for Rho: -0.3199 < Rho < 0.1633