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Re: lorenz curve
Posted:
Nov 25, 2005 1:56 AM


Here's my code snippet for calculating the Lorenz curve (for wavelet detail coefficients D  used for determining a threshold for denoising): nD=length(D); Dsort=sort(abs(D)); E=cumsum(Dsort.^2); E=E/E(end); p=[0:nD1]'/(nD1); plot(p,E)
What is the "gini coefficient"? I'm not familiar with that. Is it the point on the curve where gain in parsimony matches loss of energy? If so: % Find point where tangent touches dE=[0;(E(3:nD)E(1:nD2))/(2*p(2));inf]; [dE,indx]=unique(dE); ide=round(interp1(dE,[1:length(dE)]',1)); % Denoising threshold lamL=Dsort(indx(ide));



