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

@article{Sloczynski2020WhenSW, title={When Should We (Not) Interpret Linear IV Estimands as Late?}, author={Tymon Sloczy'nski}, journal={SSRN Electronic Journal}, year={2020} }

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…

## 14 Citations

### Empirical Decomposition of the IV–OLS Gap with Heterogeneous and Nonlinear Effects

- EconomicsThe Review of Economics and Statistics
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This study proposes an econometric framework to interpret and empirically decompose the difference between IV and OLS estimates given by a linear regression model when the true causal effects of…

### Phase transition of the monotonicity assumption in learning local average treatment effects

- Economics
- 2021

We consider the setting in which a strong binary instrument is available for a binary treatment. The traditional LATE approach assumes the monotonicity condition stating that there are no defiers (or…

### When is TSLS Actually LATE?

- EconomicsSSRN Electronic Journal
- 2022

Linear instrumental variable estimators, such as two-stage least squares (TSLS), are commonly interpreted as estimating positively weighted averages of causal effects, referred to as local average…

### Doubly Robust Estimation of Local Average Treatment Effects Using Inverse Probability Weighted Regression Adjustment

- Mathematics, EconomicsSSRN Electronic Journal
- 2022

: We revisit the problem of estimating the local average treatment eﬀect (LATE) and the local average treatment eﬀect on the treated (LATT) when control variables are available, either to render the…

### Included and Excluded Instruments in Structural Estimation

- Economics
- 2022

We consider the choice of instrumental variables when a researcher’s structural model may be misspecified. We contrast included instruments, which have a direct causal effect on the outcome holding…

### A badie ’ s K appa and W eighting E stimators of the L ocal A verage T reatment E ffect *

- Economics
- 2022

In this paper we study the ﬁnite sample and asymptotic properties of various weighting estimators of the local average treatment e ﬀ ect (LATE), several of which are based on Abadie (2003)’s kappa…

### Abadie's Kappa and Weighting Estimators of the Local Average Treatment Effect

- Mathematics, EconomicsSSRN Electronic Journal
- 2022

In this paper we study the ﬁnite sample and asymptotic properties of various weighting estimators of the local average treatment e ﬀ ect (LATE), several of which are based on Abadie (2003)’s kappa…

### The Value of Piped Water and Sewers: Evidence from 19th Century Chicago

- Economics
- 2022

We estimate the impact of piped water and sewers on property values in mid-19th century Chicago. The cost of sewer construction depends sensitively on imperceptible variation in grade, and such…

### An Omitted Variable Bias Framework for Sensitivity Analysis of Instrumental Variables

- EconomicsSSRN Electronic Journal
- 2022

We develop an “omitted variable bias” framework for sensitivity analysis of instrumental variable (IV) estimates that naturally handles multiple “side-eﬀects” (violations of the exclusion restriction…

### Two-Way Fixed Effects and Differences-in-Differences with Heterogeneous Treatment Effects: A Survey

- Economics, MathematicsSSRN Electronic Journal
- 2021

Linear regressions with period and group ﬁxed eﬀects are widely used to estimate policies’ eﬀects: 26 of the 100 most cited papers published by the American Economic Review from 2015 to 2019 estimate…

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