用stata回归过程中总是出现 2018year omitted because of collinearity
尝试了删除2018年度样本进行回归 报告2017year omitted because of collinearity
也就是说会把样本中最后一个年度的数据省略●部分数据如下:
code year LnNRules LC1 LSize LROA LLev
4 2011 5.1179938 .57302374 19.909551 .109659 .298574
4 2012 4.6821312 .86593461 19.909551 .04683 .294935
4 2013 5.164786 1.5623491 19.909551 .040506 .232528
4 2014 4.4773368 1.4114643 19.909551 .023938 .403239
4 2015 4.4543473 .84336748 19.909551 .046189 .534754
4 2016 4.5643482 2.1100365 19.909551 .0172 .590402
8 2016 4.5643482 .5276531 22.001238 .052909 .189809
8 2017 3.871201 .25741955 22.826504 .064758 .246583
8 2018 4.1588831 .29551584 23.091481 .08331 .326949
9 2013 5.164786 .89333662 23.301308 .023331 .643669
9 2014 4.4773368 .92708773 23.334203 .03263 .628798
9 2015 4.4543473 .62460514 23.412846 .032091 .628934
9 2016 4.5643482 .36965225 23.619947 .053324 .638202
9 2017 3.871201 1.1783509 23.79702 .0194 .623791
9 2018 4.1588831 1.4794874 24.023149 .011924 .633121
●回归代码:reg LC1 LnNRules LSize LROA LLev i.industry i.year,r
●回归结果如下:
note: 2018.year omitted because of collinearity
Linear regression Number of obs = 8,077
F(85, 7988) = .
Prob > F = .
R-squared = 0.2020
Root MSE = .69991
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| Robust
LCTB1 | Coef. Std. Err. t P>|t| [95% Conf. Interval]
-------------+----------------------------------------------------------------
LnNRules | .252247 .1271335 1.98 0.047 .0030322 .5014619
LSize | -.0009098 .0100226 -0.09 0.928 -.0205568 .0187372
LROA | -4.451002 .25409 -17.52 0.000 -4.949085 -3.95292
LLev | .3854127 .063247 6.09 0.000 .2614321 .5093933
|
industry |(省略)
year |
2009 | -.0966433 .1607174 -0.60 0.548 -.4116913 .2184046
2010 | -.0819111 .1105514 -0.74 0.459 -.2986207 .1347985
2011 | -.1945658 .1229863 -1.58 0.114 -.435651 .0465194
2012 | -.1208628 .0702732 -1.72 0.085 -.2586166 .0168909
2013 | -.2024836 .1288414 -1.57 0.116 -.4550464 .0500791
2014 | .0017373 .0485483 0.04 0.971 -.09343 .0969046
2015 | .0240774 .0458855 0.52 0.600 -.06587 .1140249
2016 | -.0131183 .0575601 -0.23 0.820 -.1259511 .0997146
2017 | .1505021 .0459511 3.28 0.001 .060426 .2405782
2018 | 0 (omitted)
|
_cons | -.9643322 .5979036 -1.61 0.107 -2.136379 .207715
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感谢感谢!