我的问题是:year变量原先是红色,格式是“2001-12-31”,我用encode 已经使其变蓝色了,现在回归要用,下面我试了好几次的过程,请哪位诊断诊断。
. xtreg cost tyconverg roa herfindal3 zczz ldblv lntass mb1 xihi1 tobin1 lever1 tasset glzf1 if year1==2003,fe
insufficient observations
r(2001);
. xtreg cost tyconverg roa herfindal3 zczz ldblv lntass mb1 xihi1 tobin1 lever1 tasset glzf1 if year1==2003-12-31,fe
insufficient observations
r(2001);
. xtreg cost tyconverg roa herfindal3 zczz ldblv lntass mb1 xihi1 tobin1 lever1 tasset glzf1 if year==2003-12-31,fe
type mismatch
r(109);
. xtreg cost tyconverg roa herfindal3 zczz ldblv lntass mb1 xihi1 tobin1 lever1 tasset glzf1 if year==2003, fe
type mismatch
r(109);
. xtreg cost tyconverg roa herfindal3 zczz ldblv lntass mb1 xihi1 tobin1 lever1 tasset glzf1 if year=2003, fe
type mismatch
r(109);
. xtreg cost tyconverg roa herfindal3 zczz ldblv lntass mb1 xihi1 tobin1 lever1 tasset glzf1 if year1=2003, fe
invalid syntax
r(198);