{* *! version 1.0.2  30mar2007}{...}
{phang}
{opt vce(vcetype)} specifies the type of standard error reported, which
includes types that are derived from asymptotic theory, that are robust to
some kinds of misspecification, and that allow for intragroup correlation;
see {helpb xt_vce_options:[XT] {it:vce_options}}. 
{p_end}
