http://deathstar.tamu.edu/upload_images/43/STATA9.htm
里面有提到,This file demonstrates some of STATA's procedures for doing censored and truncated regression.
In particular, we estimate a lower limit censored regression (i.e., Tobit), Cragg's model that assumes a heterogenous censoring process, Heckman's incidential truncation model for dealing with sample selection bias, and truncated regression.