When Should We (Not) Interpret Linear IV Estimands as Late?

  title={When Should We (Not) Interpret Linear IV Estimands as Late?},
  author={Tymon Sloczy'nski},
  journal={SSRN Electronic Journal},
In this paper I revisit the interpretation of the linear instrumental variables (IV) estimand as a weighted average of conditional local average treatment effects (LATEs). I focus on a practically relevant situation in which additional covariates are required for identification but the reduced-form and first-stage regressions are possibly misspecified as a result of neglected heterogeneity in the effects of the instrument. If we also allow for conditional monotonicity, i.e. the existence of… 

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