st: Negative incomes and income components using -sgini-

[David Coyne <djcoyne@gmail.com>]

Hello,

I've been attempting to decompose the Gini coefficient of a measure C,
where C=A-B. I have two questions related to this. First, if C has some
values that are negative, how does this affect the interpretation of the
Gini coefficient? Second, if B is nonnegative, (i.e. using -sgini- would
have me use C=A + (-B), so if (-B) < 0 for all observations) thus leaving
me with a negative contribution (s*g*r) to the Gini coefficient of C, does
that mean that B has an equalizing effect on C? Not sure of the
interpretation of this. Any insight and/or advice would be appreciated!

Thanks in advance,

--
David Coyne
*
*   For searches and help try:
*   http://www.stata.com/help.cgi?search
*   http://www.stata.com/support/statalist/faq
*   http://www.ats.ucla.edu/stat/stata/