The MODECLUS Procedure

(View the complete code for this example.)

This example uses distance data and illustrates the use of the TRANSPOSE procedure and the DATA step to fill in the upper triangle of the distance matrix. A data set containing a table of flying mileages between 10 U.S. cities is available in the Sashelp library. The results are displayed in Output 79.2.1 through Output 79.2.3.

The following statements produce Output 79.2.1:

title 'Modeclus Analysis of 10 American Cities';
title2 'Based on Flying Mileages';

*-----Fill in Upper Triangle of Distance Matrix---------------;
proc transpose data=sashelp.mileages out=tran;
   copy city;
run;

data mileages(type=distance drop=col: _: i);
   merge sashelp.mileages tran;
   array var[10] atlanta--washingtondc;
   array col[10];
   do i = 1 to 10;
      var[i] = sum(var[i], col[i]);
   end;
run;

*-----Clustering with K-Nearest-Neighbor Density Estimates-----;
proc modeclus data=mileages all m=1 k=3;
   id CITY;
run;

The following statements produce Output 79.2.2:

*------Clustering with Uniform-Kernel Density Estimates--------;
proc modeclus data=mileages all m=1 r=600 800;
   id CITY;
run;

The following statements produce Output 79.2.3:

*------Clustering Neighborhoods Extended to Nearest Neighbor--------;
proc modeclus data=mileages list m=1 ck=2 r=600 800;
   id CITY;
run;