Obtaining row (individual subject) coordinates in a multiple correspondence analysis (MCA)


You can get row coordinates in an MCA by performing a simple correspondence analysis of a table in which the columns are the same as in the MCA (that is, they are the columns of the Burt table), but the rows are simply the observations of the data set.

Using the MCA example in the CORRESP procedure chapter of the SAS/STAT® User's Guide, remove the MCA option to get a simple, rather than multiple, correspondence analysis. Add the BINARY option, which causes each observation of the data set to be treated as a row of the table.

proc corresp data=Cars outc=coor binary;
   tables origin size type income home marital sex;
   run;

Instead of using the BINARY option, you can also specify a row variable which uniquely identifies the rows if such a variable exists in the data. The following statements perform the same analysis by creating a row identifier variable (N) for the Cars data set and specifying it as the row variable.

data Cars2;
   set Cars; N=_n_;
   run;

proc corresp data=Cars2 outc=coor;
   tables N, origin size type income home marital sex;
   run;