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Substitution and dropout bias in social experiments : a study of an influential social experiment
Heckman, James J., (2000)
Learning about social programs from experiments with random assignment of treatments
Manski, Charles F., (1995)
Social experiments : theory and evidence
Heckman, James J., (1996)
The sensitivity of experimental impact estimates : evidence from the national JTPA study
Ashenfelter's dip and the determinants of participation in a social program : implications for simple program evaluation strategies
Heckman, James J., (1995)
Accounting for dropouts in evaluations of social experiments
Heckman, James J., (1994)