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help for ^sumdist^                             (STB-48: sg104)
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Distribution summary statistics, by quantile group
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^sumdist^ varname [weight] [^if^ exp] [^in^ range] [^,^
			 ^n^gps^(^#^)^ ^qgp(^gpname^)^ ]

^fweight^s and ^aweight^s are allowed; see help @weights@.


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

^sumdist^ estimates distributional summary statistics commonly used
by income distribution analysts, complementing those available via
^pctile^, ^xtile^, and ^summarize, detail^.  
For variable x and distribution function F(x), the statistics are 
(1) quantiles k = 1,2,...,m-1, for m = # quantile groups; 
(2) the quantiles expressed as a percentage of median(x);
(3) the quantile group share of x in total x (group income share, %); 
(4) the cumulative quantile group shares of total x (with 
    cumulation in ascending order of x), i.e. the Lorenz ordinates 
    L(p) at each p_k = F(x_k) for quantile points x_k; and 
(5) the generalised Lorenz ordinates at each p_k = F(x_k), i.e.
     GL(p_k) = mean(x)*L(p_k).


Options
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^ngps(^#^)^ specifies the number of quantile groups. Valid values
              are integers in the range (0,100]. The default is 10.
^qgp(^gpname^)^ creates a new categorical variable, gpname, containing
	      categories summarising quantile group membership, with
	      the number of categories equal to m.


Examples
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   . ^sumdist x^  
   . ^sumdist x, n(5)^
   . ^sumdist x [w=wgt] if x > 0^
   . ^sumdist x, n(20) qgp(quantgp)^


Author
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      Stephen P. Jenkins 
      Institute for Social and Economic Research
      University of Essex, Colchester CO4 3SQ, U.K.
      stephenj@@essex.ac.uk


Reference
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Cowell, F.A. (1995) Measuring Inequality (second edition).
	Prentice-Hall/Harvester-Wheatsheaf, Hemel Hempstead.


Also see
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    STB: STB-48 sg104
 Manual: [R] pctile, [R] summarize, [R] cumul
On-line: help for @pctile@, @xtile@, @summarize@, @cumul@ 
         @glcurve@ (if installed)