Huber variance estimates                                         (STB-9: sg8.1)
------------------------

	^hereg^    [depvar [indepvars] [weight] [^if^ exp] [^in^ range] ]
		[^, g^roup^(^varname^)^ ereg_options ]

^pweight^s, ^aweight^s, and ^fweight^s are allowed.

All commands share the features of estimation commands; see [4] estimate.

To reset problem-size limits, see ^help matsize^.


Description
-----------

^hereg^ estimates an exponential regression with robust standard errors based
on Huber's formula for individual-level data.  Consistent standard errors are
estimated even if the distributional assumptions are wrong, or there is
clustered sampling, or the data are weighted.


Options
-------

^group(^varname^)^ identifies the cluster to which an observation belongs.  Cases
    with the same value of varname are assumed to be drawn from the same
    cluster.  The data need not be sorted by varname.

ereg_options are any of the options allowed by ^ereg^; see ^help weibull^.


Examples
--------

 . ^hereg time age sex, group(clinic) dead(notcens) ^


Also see
--------

    STB:  sg8.1, sg8 (STB-9)
 manual:  [5s] huber, [5s] weibull, [4] estimate
On-line:  ^help^ for ^weibull^, ^predict^, ^test^