Hi all,
I found this interesting macro at a paper for imputing missing values using the nearest neighbor technique, my problem is that this macro contains a part done with proc iml , a procedure that i dont have in my sas base,
Ho would be possible to lets say translate it into normal code script?
Kind regards and thnx in advance, the macro is:
%MACRO NNI(INDATA=, /*INPUT DATA SET(INCLUDING LIBRARY NAME) */
MISSVAR=, /*INPUT SINGLE VARIABLE WITH MISSING DATA*/
RESPVAR=, /*RESPONSE VARIABLE*/
IDVAR=, /*SUBJECT VARIABLE*/
OUTDATA= /*OUTPUT DATA SET WITH COMPLETE DATA*/
);
DATA OBSY_MISSX;
SET &INDATA;
IF &MISSVAR=.;
KEEP &IDVAR &RESPVAR;
RUN;
PROC MEANS DATA=&INDATA N NMISS NOPRINT;
VAR &MISSVAR;
OUTPUT OUT=OBSN N=OBSX NMISS=MISSX;
RUN;
DATA _NULL_;
SET OBSN;
CALL SYMPUT('OBSN',OBSX);
CALL SYMPUT('MISSN',MISSX);
RUN;
DATA SIMDATA_NOMISS;
SET &INDATA;
IF &MISSVAR NE .;
RUN;
PROC IML;
USE SIMDATA_NOMISS;
READ ALL VAR {&MISSVAR} INTO XMAT;
READ ALL VAR {&RESPVAR} INTO YMAT;
6
USE OBSY_MISSX;
READ ALL VAR {&IDVAR &RESPVAR} INTO MISSMAT;
TXMAT=T(XMAT);
TYMAT=T(YMAT);
DISTANCE=J(&MISSN,&OBSN,.);
MIND=J(&MISSN,1,.);
MISSVAR=J(&MISSN,&OBSN,.);
IMP=J(&MISSN,1,.);
DO I = 1 TO &MISSN;
DO J = 1 TO &OBSN;
DISTANCE[I,J]=ABS(MISSMAT[I,2]-TYMAT[,J]);
END;
MIND[I,]=MIN(DISTANCE[I,]);
END;
DO I = 1 TO &MISSN;
DO J = 1 TO &OBSN;
IF DISTANCE[I,J]=MIND[I,] THEN MISSVAR[I,J]=TXMAT[,J];
END;
IMP[I,]=MISSVAR[I,:];
END;
CNAME={"&IDVAR" "&RESPVAR" "&MISSVAR"};
IMPX=MISSMAT||IMP;
CREATE NNI FROM IMPX[C=CNAME];
APPEND FROM IMPX;
QUIT;
DATA &OUTDATA;
MERGE &INDATA NNI;
BY &IDVAR;
RUN;
%MEND;
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