{smcl}
{* June 2007/August 2007}{...}
{cmd:help descogini}{right:(SJ7-4: st0100_1; SJ6-1: st0100)}
{hline}

{title:Title}

{p2colset 5 18 20 2}{...}
{p2col :{hi:descogini} {hline 2}}Gini decomposition by income source{p_end}
{p2colreset}{...}


{title:Syntax}

{p 8 17 2}
{cmd:descogini} {varlist}  {ifin} [{cmd:,} {opt d(#)} {opt bar}]


{title:Description}

{pstd} 
This command decomposes the Gini coefficient by income source using the
approach described in Lerman and Yitzhaki (1985) and Stark, Taylor
and Yitzhaki (1986), which allows calculation of the impact that a
marginal change in a particular income source will have on inequality.


{title:Options}

{phang}
{opt d(#)} specifies the number of decimal places to be reported in the
table of results. The default is {cmd:d(4)}.

{phang}
{cmdab:bar} specifies that a vertical bar should be included before each
output field. Such output can be pasted into Microsoft Word as text and
converted into a table using the vertical bars as separators.


{title:Remarks}

{pstd} 
The first variable in {varlist} should always be the variable that
captures total income. The order in which the income sources are
included in the syntax does not matter.{p_end}

{pstd} 
The last column of the table of results (% Change) refers to the impact
that a 1% change in the respective income source will have on
inequality. Four additional elements are included in the table of
results: the share of each income source in total income (Sk), the
source Gini (Gk), the Gini correlation of income from source k with the
distribution of total income (Rk), and the share of each income source
in total inequality.{p_end}
 
{pstd} 
Bootstrapped standard errors of the estimated impacts on inequality can
easily be obtained using this command (see examples below).  {p_end}
 

{title:Examples}

{phang2}{cmd:. descogini totinc farminc ofarminc transinc}

{phang2}{cmd:. descogini totinc farminc ofarminc transinc, d(5)}

{pstd}To obtain bootstrapped standard errors and confidence intervals:

{phang2}{cmd:. bootstrap "descogini totinc farminc ofarminc transinc" _b} 

{phang2}{cmd:. bootstrap "descogini totinc farminc ofarminc transinc" _b Gini=gtotal} {p_end}


{title:Author}

{p 4 8 2}Alejandro Lopez-Feldman{p_end}
{p 4 8 2}Escuela de Economia{p_end}
{p 4 8 2}Universidad de Guanajuato{p_end}
{p 4 8 2}Email: {browse "mailto:lopezfeldman@gmail.com": lopezfeldman@gmail.com}


{title:Citation}

{p 4 4 2}{cmd:descogini} is not an official Stata command. It is a free
contribution to the research community, like a paper. Please cite the
Lopez-Feldman (2006) paper. {p_end}


{title:References}

{phang}Lerman, R.I. and S. Yitzhaki. 1985. Income inequality effects by
income source: A new approach and applications to the United States.
{it:Review of Economics and Statistics} 67: 151{c -}156.

{phang}Lopez-Feldman, A. 2006. 
Decomposing inequality and obtaining marginal effects.
{it:The Stata Journal} 6(1): 106{c -}111.

{phang}Stark, O., J.E. Taylor and S. Yitzhaki. 1986. Remittances and
inequality. {it:Economic Journal} 96: 722{c -}740.


{title:Also see}

{psee}
Online: {helpb inequal} (if installed), {helpb ineqdeco} (if installed),
        {helpb ginidesc} (if installed), {helpb ineqfac} (if installed)
{p_end}