Gijs:

You might find the code below helpful (this should run thri SAS v8.2).

-Gerry

Gerard T. Pauline Computer Systems, DoIT Pace University

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/**********************************************************************/ /*************************** Pace University **************************/ /****************** Department of Academic Computing ******************/ /**********************************************************************/ /* */ /* Program Name: Ginicode (source for the GINI macro) */ /* */ /* Language: SAS (6.07 ) */ /* */ /* Date Implemented: 03/03/93 */ /* */ /* Program Version: 1.00 */ /* */ /* Program Author: Mark Keintz (Gini Methodology) */ /* Computer Group Manager */ /* Population Studies Center */ /* University of Pennsylvania / 6298 */ /* 3718 Locust Walk */ /* Philadelphia, Pa 19104-6290 */ /* (215) 898-6713 */ /* Mkeintz @ Mail.Sas.Upenn.Edu */ /* */ /* Gerard T. Pauline (Macro Shell) */ /* Mgr, Internet/DB Applications */ /* Computer Systems, DoIT */ /* Pace University */ /* 1 Pace Plaza */ /* New York, NY 10038 */ /* (212) 346-1706 */ /* Gerry@Pace.Edu */ /* */ /**********************************************************************/ /************************* Purpose of Program *************************/ /**********************************************************************/ /* */ /* This program computes the GINI concentration coefficient; option- */ /* ally, if requested, it will also plot a Lorenz Curve. The coef- */ /* ficient is generated by the following methodology: */ /* */ /* 1- Compute the total for the variable to be 'GINIed' by */ /* group to generate 'X' (num of cases) and 'Y' (sum of */ /* the variable to be ginied) values. */ /* */ /* 2- Compute the representation of the variable total (of */ /* the variable to be 'GINIed') and the cases in each */ /* group (X and Y). */ /* */ /* 3- Compute the ratio in each group (y / x) */ /* */ /* 4- Sort by the ratio of y / x . */ /* */ /* 5- Generate GINI coefficient and the coordinates for the */ /* Lorenz Curve. */ /* */ /* The dataset may contain values that are discrete (with a requisite */ /* Id variable) or grouped. */ /* */ /* Output of the coefficient occurs in one of two ways: if the plot- */ /* ting of the Lorenz Curve is requested, the coefficient is display- */ /* at the top of the plot; if the curve is not requested, the coef- */ /* ficient is displayed on the user's terminal (if submission is by */ /* VMBatch, the coefficient is written to a LISTING file. */ /* */ /* @@ Note: */ /* */ /* This code is compiled and stored in the file 0SASMACR GINIMAC. */ /* If the data source is one of the online databases, the macro */ /* is loaded as part of the ACCESS macro system. If the source of */ /* data is not one of the online databases, the macro is invoked */ /* by 'including' the file GINICOEF SAS in the source program, */ /* which contains code to load the GINI and DEVICE macros. */ /* */ /**********************************************************************/ /************************** Acknowledgements **************************/ /**********************************************************************/ /* */ /* The methodology to compute the GINI coefficient was developed by */ /* Mark Keintz, and his assistance in the implementation of this code */ /* is gratefully acknowledged by the Department of Academic Computing */ /* at Pace University. */ /* */ /**********************************************************************/ /************************ Input And Output Files **********************/ /**********************************************************************/ /* */ /* A temporary or permanent SAS dataset containing one or more var- */ /* iables to be 'GINIed'. */ /* */ /**********************************************************************/ /********************* Subroutines And Procedures *********************/ /**********************************************************************/ /* */ /* None */ /* */ /**********************************************************************/ /**************** External References And Dependencies ****************/ /**********************************************************************/ /* */ /* %Device - SAS macro to assign a graphics capable output device */ /* (3179G, 3278-2PS, 3279G2 & G3, Kermit, 3287-2C, 4045 */ /* Xerox lasers) */ /* */ /* This program uses the Stored Macro Facility under SAS 6.07 to */ /* compile and store the GINI macro. */ /* */ /**********************************************************************/ /***************************** Update Log *****************************/ /**********************************************************************/ /* */ /* 1.) 00/00/00 */ /* */ /**********************************************************************/

Options MAUTOSOURCE MSTORED SASMSTORE=GINIMAC ;

%Macro GINI (DS= , /* Input Dataset */ ID= , /* Id (Grouping) Variable */ VAR= , /* Variable To 'Gini' */ DEVICE= , /* Graphics Output Device */ GSIZE=72, /* Graph Size (Text Graphics Only) */ GRAPH=N) /* Control (N-No Plot, T-Text Grp, S-SASGraph) */ / Store ; /* Compile And Store The Macro In GINIMAC */

%Let VAR = %Upcase(&VAR) ; /* Uppercase For Title Display */

/*----------------- Compute Totals For &VAR By &ID ----------------*/

Proc SUMMARY Data=&DS ; Class &ID ; /* Group By This Variable */ Var &VAR ; /* For This Variable */ Output Out=GINISUM N=X Sum=Y ; /* N Is # of Cases, Y is &VAR Sum */ Run ;

/*-------------- Compute Ratio of X & Y In Each Group -------------*/

Data GINIDATA (Keep=X Y RATIO) ; Set GINISUM ;

Retain TOTAL_X TOTAL_Y ;

If (_TYPE_ = 0) Then Do ; TOTAL_X = X ; /* Grand Total of X */ TOTAL_Y = Y ; /* Grand Total of Y */ Delete ; /* Remove The Type 0 Record From Dataset */ End ;

Y = Y / TOTAL_Y ; /* Current Y For This Record */ X = X / TOTAL_X ; /* Current X For This Record */ RATIO = Y / X ; /* Ratio of Y To X For This Record */

Run ;

/*----------- Sort Records For Lorenz Curve Computation -----------*/

Proc SORT Data=GINIDATA ; By RATIO ; Run ;

/*----- Generate GINI Coefficient And Lorenz Curve Coordinates ----*/

Data LORENZ (Drop=CUM_AREA) ; Set GINIDATA End=EOF ;

Retain CUM_X CUM_Y CUM_AREA 0 ;

/*--------------- Compute Lorenz Curve Coordinates --------------*/

CUM_AREA = CUM_AREA + X * (2 * (CUM_X - CUM_Y) + (X - Y)) ; CUM_X = CUM_X + X ; CUM_Y = CUM_Y + Y ;

/*--------- At End of File, Compute The GINI Coefficient --------*/

If (EOF) Then Do ; GINI = CUM_AREA / (CUM_X * CUM_Y) ; /* Gini Coefficient */ Call SYMPUT ('GINICO', GINI) ; /* Assign To Macro Variable */ End ;

Run ;

/*-- Display The Coefficient, And If Requested, The Lorenz Curve --*/

%If (&GRAPH = S) %Then /* Plot Lorenz Curve With SAS Graph */ %Do ; %Device (&DEVICE) /* Assign Graphics Output Device */

Symbol1 Color=RED H=2 V=DOT I=J ; Axis1 Label=('Group') ; Axis2 Label=('Concentration') ; Title1 H=2 F=SWISSB 'Lorenz Curve' ; Title3 H=1 F=SWISSB Box=1 "Gini Coefficient For The Variable &VAR Is &GINICO" ;

Proc GPLOT Data=LORENZ ; Plot CUM_Y * CUM_X / Vaxis=AXIS1 Haxis=AXIS2 Caxis=BLUE ; Run ; %End ;

%Else %If (&GRAPH = T) %Then /* Plot Lorenz Curve With Text Graphics */ %Do ; Options LS=&GSIZE NODATE ; Proc PLOT Data=LORENZ Nolegend ; Plot CUM_Y * CUM_X ; Label CUM_Y = 'Group' CUM_X = 'Concentration' ; Title1 'Lorenz Curve' ; Title3 "Gini Coefficient For The Variable &VAR Is &GINICO" ; Run ; %End ;

%Else %If (&GRAPH = N) %Then /* Display GINI Coefficient Only */ %Do ; %Let ID = %Substr(&SYSJOBID, 1, 5) ; /* User Id */ Options LS=&GSIZE NODATE ; Filename GINI Terminal ; Data _NULL_ ; %If (&ID ^= BATCH) %Then /* From The User's CMS Acct */ %Do ; File GINI ; /* Output To Terminal */ %End ; %Else /* Batch Submission */ %Do ; File PRINT Notitle ; /* Output To A Listing File */ %End ; Length GVR $ 8 /* Variable That Was GINIed */ GCO $ 15 /* Gini Coefficient */

D1

D2 D3 $ 65 ; GVR = Symget('VAR') ; /* Retrieve Value of &VAR */ GCO = Symget('GINICO') ; /* Retrieve Value of &GINICO */ D1 = 'GINI Coefficient for the variable ' || Trim(GVR) || ' is ' || GCO ; D2 = Repeat('-', Length(D1)-1) ; D3 = D2 ; Put / @1 D2 / @1 D1 / @1 D3 / ; /* Write To Output Unit */ Run ; %End ;

%Mend GINI ;

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Gijs Dekkers wrote: > > I am looking for a macro/program which calculates (and plots) Lorenz > curves. Can anybody help me? > > Thanks in advance, > > Gijs > > -- > Dr. Gijs Dekkers > Federaal Planbureau > Algemene Directie > Kunstlaan 47-49 > B 1000 Brussel > ++32/(0)2/5077413 > fax 7373