. Author manuscript; available in PMC: 2019 Mar 11.

Published in final edited form as: Am Econ J Appl Econ. 2018 Jan;10(1):307–341. doi: 10.1257/app.20160404

Table 8.

OLS and IV Estimates of Lead and Third Grade Scores Instrument Is Predicted Certificate

	OLS (1)	IV (2)	IV (3)
Dependent variable: Below proficient in reading
Geometric mean of lead	0.0075 [0.0005]	0.0352 [0.00938]	0.0270 [0.0144]
Observations	70,678	70,678	70,637
R²	0.090
Dependent variable: Reading score
Geometric mean of lead	−0.332 [0.0199]	−0.936 [0.340]	−0.931 [0.516]
Observations	70,678	70,678	70,637
R²	0.223
Dependent variable: Below proficient in math
Geometric mean of lead	0.0056 [0.0006]	0.0143 [0.0104]	0.00999 [0.0157]
Observations	70,625	70,625	70,584
R²	0.103
Dependent variable: Math score
Geometric mean of lead	−0.217 [0.0187]	−0.149 [0.317]	−0.431 [0.471]
Observations	70,625	70,625	70,584
R²	0.225
Additional controls:
Census tract, year of birth, month of birth fixed effects	Yes	Yes	Yes
Average score in grade × school (leave-out mean)			Yes
Percent below proficient in grade × school (leave-out mean)			Yes
Race specific linear time trend			Yes
Free lunch specific linear time trend			Yes

Notes: Standard errors clustered on census tract are shown in brackets. Instrument for child’s lead level is whether the child is predicted to live in a home with a lead certificate at the time they were first tested, based on the regression presented in Table 5, column 2. All other covariates in Table 3, column 3, also included.