arXiv:1209.1588v1 [stat.ME] 7 Sep 2012 Victoria Zinde-Walsh ∗ McGill University and CIREQ victoria.zinde-walsh@mcgill.ca January 23, 2018 1 ∗ The support of the Social Sciences and Humanities Research Council of Canada (SSHRC) and the Fonds qu´ ebecois de la recherche sur la soci´ et´ e et la culture (FRQSC) is gratefully acknowledged. Identification and well-posedness in nonparametric models with independence conditions