::
|
tags ·
relations ·
groups ·
popular
|
help · blog · about |
| login · register |
| Authors: | James J. Heckman and Richard Robb |
| URL: | http://www.sciencedirect.com/science/article/B6VC0-4582JY6-2T/2/dc1d6c70dda783d15830b44950bce914 |
| Description: | Journal of Econometrics |
| Tags: | imported |