看到有人说大N小T的面板数据,又存在序列相关的话,可以用动态面板数据
但是工具变量的选取很困惑,尤其是先决变量和内生变量,外生变量的界定,拿不准
试图选取工具变量后检验结果如下:
Arellano-Bond test for AR(1) in first differences: z = -17.94 Pr > z = 0.000
Arellano-Bond test for AR(2) in first differences: z = 1.62 Pr > z = 0.106
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Sargan test of overid. restrictions: chi2(91) = 245.31 Prob > chi2 = 0.000
(Not robust, but not weakened by many instruments.)
好像Sargan检验说明工具变量选取不当,P值得多少才能说明工具变量适当呢?
盼望回答,先行谢过!~