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An instrument $Z$ has $\operatorname{Cov}(Z, Y) = 0.6$ and $\operatorname{Cov}(Z, X) = 0.4$ . What is the instrumental variables estimate of the effect of $X$ on $Y$ ?

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Identification: endogeneity, instruments and panel methods

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An instrument ZZZ has Cov⁡(Z,Y)=0.6\operatorname{Cov}(Z, Y) = 0.6Cov(Z,Y)=0.6 and Cov⁡(Z,X)=0.4\operatorname{Cov}(Z, X) = 0.4Cov(Z,X)=0.4. What is the instrumental variables estimate of the effect of XXX on YYY?

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An instrument $Z$ has $\operatorname{Cov}(Z, Y) = 0.6$ and $\operatorname{Cov}(Z, X) = 0.4$ . What is the instrumental variables estimate of the effect of $X$ on $Y$ ?