Tied values are randomized. From the helpfile:
"Note: ties in the sort index (i.e., identical sorting values) are broken in
an arbitrary (i.e., random) order, unless the stable option is specified."
You might try:
sort f1, stable
sort f2, stable
Hope this helps,
Scott
> -----Original Message-----
> From: [email protected] [mailto:owner-
> [email protected]] On Behalf Of louis boakye-yiadom
> Sent: Monday, March 21, 2005 6:09 AM
> To: [email protected]
> Subject: st: Changing -correlate- results
>
> Dear All,
> Apologies for the garbled form of my last mail.
> A -correlate- command in my do file gives slightly different results each
> time the file is executed. For example, for the last three times the file
> was executed, the correlation coefficient between the same two variables
> (rankf1 and rankf2) were as follows: 0.7466, 0.7499, and 0.7524. I'm
> baffled
> by this, and I don't find any explanation from the -help- for -correlate-.
> I've provided excerpts of the do file. Any help will be appreciated.
> Thank you.
>
> use isocomb_indices, clear;
> sort f1;
> list region district dmrd dmkt dpt djss dchp fl, clean header(50);
> gen rankf1=_n;
> sort f2
> list region district pwrd pwmkt1 pwmkt2 pwjss pwchp f2, clean header(50);
> gen rankf2=_n;
> bysort region: list region district nc f1 rankf1 f2 rankf2, clean mean(f1
> rankf1 f2 rankf2);
> correlate rankf1 rankf2;
> drop rankf1 rankf2;
> sort region district;
> save isocomb_indices, replace;
> clear;
> log close;
> exit;
>
> Louis
>
>
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