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Estmating and Interpreting Models with Endogenous Treatment Effects: The Relationship between Competing Estimators of the Union Impact on Wages.
Vella, F., (1993)
Estimating the Impact of Endogenous Unions Choice on Wages Using Panel Data.
Vella, F., (1992)
Estimating and testing Simultaneous Equation Panel Data Models with Censored Endogenous Variables.