st: question about quantiles in summarize

[Richard Goldstein <richgold@ix.netcom.com>]

Below is a listing of a short data set and the detail summarize; it is 
exceedingly hard to understand where some of the quantiles come from (e.g., 
the 25th percentile) and any help would be greatly appreciated -- I used an 
up-to-date version 9.2 on Windows XP (SP2).

Rich

. li var1, clean

        var1
  1.    -.07
  2.    -.09
  3.     -.3
  4.     -.4
  5.    -.48
  6.    -.48
  7.    -.51
  8.    -.57
  9.    -.57
 10.    -.57
 11.    -.73
 12.    -.75
 13.   -1.08
 14.   -1.08
 15.   -1.08
 16.   -1.11
 17.    -1.2
 18.    -1.4
 19.     .47
 20.     .49
 21.     .49
 22.     .54
 23.     .67
 24.     .69
 25.     .78
 26.     .87
 27.     .94
 28.     .96
 29.    1.15
 30.     1.2
 31.    1.46
 32.    1.48

. su var1, d

                            var1
-------------------------------------------------------------
      Percentiles      Smallest
 1%         -1.4           -1.4
 5%         -1.2           -1.2
10%        -1.08          -1.11       Obs                  32
25%         -.65          -1.08       Sum of Wgt.          32

50%        -.195                      Mean            -.00875
                        Largest       Std. Dev.       .867989
75%         .735           1.15
90%         1.15            1.2       Variance       .7534048
95%         1.46           1.46       Skewness       .1382741
99%         1.48           1.48       Kurtosis       1.709454


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