191 IV14 Weak instruments

Summary unavailable. Hi everyone, my name is Lydia and this is what I wish they told me about econometrics and introduction. We spent several videos learning what makes a valid instrument but even when an instrument satisfies both relevance and the exclusion, condition, one important question remains does it affect x strongly enough to be useful? Okay, so an instrument can be technically valid, satisfying all the conditions and still produce unreliable estimates and that's exactly the weak instrument problem. So the relevance condition requires you simply that the covariance between your z and x not b0. Any non-zero correlation is going to satisfy it but how strong does that correlation need to be? And the relev