在下小白,请问用R做Difference in difference双重差分模型分析的具体指令语言要
在下小白,请问用R做Difference in difference双重差分模型分析的具体指令语言要怎么写?
我找了之前有人贴的普林斯顿和Tanzan的step by step,但到了赋值虚拟变量这一步就出现Error in `$<-.data.frame`(`*tmp*`, "time", value = logical(0)) : replacement has 0 rows, data has 96,请问是啥意思?
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