-glcurve-: a program for generalised Lorenz
curves and related structures
Stephen Jenkins, University of Essex and
Philippe Van Kerm, FUNDP, Namur
The well-known Lorenz curve for a variable y plots L(p(y)) against p(y)
where p(y) is the cumulative distribution function of y and L(p(y)) is the
cumulative share of y up to p(y) (i.e. it is a plot of cumulative income
shares against cumulative population share). The generalised Lorenz curve,
is the Lorenz curve with y-ordinates multiplied by the mean of y. This tool
is frequently used by economists to present and compare income distributions
because of the relation existing between GL dominance and traditional
second-order stochastic dominance and the close link between these concepts
and social welfare comparisons.
This talk introduces glcurve, a program basically designed
to draw generalised Lorenz curves for a given continuous variable.
glcurve has two attractive features: on the one hand it is
flexible in the sense that it can be used to draw related graphs such as
Lorenz curves, concentration curves or “TIP” curves and, on the
other hand, permits easy visual dominance checks by population subgroups.
The interest of generalised Lorenz curves comparisons will be emphasised and
the simple data transformations needed to obtain related structures will
also be illustrated.
Jenkins S.P. and P. Van Kerm. 1999.
sg107: Generalized Lorenz Curves and
Related Graphs. Stata Technical Bulletin 48: 25—29.
User Group meetings