jlfx2.sas

those are some program of the sas system .and very useful when doing the statistic working .

title'美国十在城市间飞行里程的聚类分析';
data ex(type=distance); 
input(atlanta chicago denver houston losangle
      miami newyork sanfran seattle washdc)(5.)@50  city$15.;
cards;
0                                                    亚特兰大
587  0                                               芝加哥 
1212 920  0                                          丹佛
701  940  879  0                                     休斯顿
1936 1745 831  1374 0                                洛杉矶
604  1188 1726 968  2339 0                           迈阿密
748  713  1631 1420 2451 1092 0                      纽约
2139 1858 949  1645 347  2594 2571 0                 旧金山
2182 1737 1021 1891 959  2734 2408 678  0            西雅图
543  597  1494 1220 2300 923  205  2442 2329 0       华盛顿 
 ;
  proc cluster data=ex  method=average pseudo;id city;proc tree;id city;   /*类平均法*/
  proc cluster data=ex  method=centroid pseudo;id city;proc tree;id city;  /*重心法*/
  proc cluster data=ex  method=density k=3;id city;proc tree;id city;      /*密度估计法*/
  proc cluster data=ex  method=single;id city;proc tree;id city;           /*最短距离法*/
  proc cluster data=ex  method=twostage k=3;id city;proc tree;id city;     /*两阶段密度估计法*/
  proc cluster data=ex  method=ward pseudo;id city;proc tree;id city;      /*Ward最小方差法*/
  run;