stata里做psmatch2匹配后结果显示:未匹配时t大而匹配后的t值小怎么解释呢?是因为匹配方法的问题还是什么呢?
求各位大神帮忙解释解释,先谢谢啦
Note: 2 failures and 0 successes completely determined.
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Variable Sample | Treated Controls Difference S.E. T-stat
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fl4014 Unmatched | .557424066 .390793396 .166630669 .027401127 6.08
ATT | .503905656 .548013168 -.044107511 .035176708 -1.25
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