我的命令如下<br>
ivreg2h fin_risk $controls (vulnerability=),small robust
结果显示如下<br>
Too few excluded instruments: standard IV model not estimable
***** IV with Generated Instruments only *****<br>
Instruments created from Z:<br>
kaopen lngdp gdp_growth inflation leverage dummy finance efi<br>
option partial() not allowed
是因为什么呢？<br>