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Instrumental variables : response to Angrist and Imbens
Heckman, James J., (1999)
The relationship between parameters within a latent variable framework
Heckman, James J., (2000)
Instrumental variables : a study of implicit behavioral assumptions used in making program evaluations
Heckman, James J., (1997)
Estimation of limited dependent variable models with dummy endogenous regressors : simple strategies for empirical practice
Angrist, Joshua D., (2000)
Identification and Estimation of Local Average Treatment Effects
Angrist, Joshua D., (2007)