st: IV 2SLS regression

["Carlos Rodriguez" <carlosrodriguez1993@gmail.com>]

Hello list members,

I have a couple of questins regarding ivregress 2sls:

1) is it wrong to include some regressors which might be endogenous as
controls, in addition to the instrumented main endogenous explanatory
variable?

2)  can one use a LDV in an ivregress 2sls model? does it cause bias?

thanks! happy holidays
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