st: Testing two groups percentile differences/ Cendif error message

["Min Y. Tan" <mtan@learnlink.emory.edu>]

Hi all
I am trying to test the 5th 10th ...95th percentile difference between two
groups which are not necessarily normally distributed or independent. Is there
any other method other than cendif?
I am using cendif, but i get an error message:

. cendif means, by(type)
Y-variable: means
Grouped by: type
Group numbers:

       type |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |     57,293       62.45       62.45
          2 |     34,451       37.55      100.00
------------+-----------------------------------
      Total |     91,744      100.00
invalid syntax
r(198);


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