Re: PSPP-BUG: pspp bug

[Ben Pfaff]

When we looked at this in IRC, I think we were looking at the
wrong value.  You were talking about log(0) but that's involved
in "Bartlett's Test of Sphericity" not in "Kaiser-Meyer-Olkin
Measure of Sampling Adequacy".

I added
      printf ("sum_ssq_r=%e sum_ssq_a=%e\n", sum_ssq_r, sum_ssq_a);
as line 1870 of factor.c and got:
        sum_ssq_r=3.472064e+35 sum_ssq_a=1.036522e-30
so that the calculation sum_ssq_r /  (sum_ssq_r + sum_ssq_a) is
basically x / (x + 0) == 1, which seems reasonable.  What do you
see when you add that line?

John Darrington <address@hidden> writes:

> I'll take a look at it.
>
> On Wed, Apr 04, 2012 at 09:17:17AM -0700, Ben Pfaff wrote:
>      That seems bad.  "1.00" and NaN are pretty different.  Do you
>      think it's worth looking into the calculations, or should we just
>      ignore this difference as we have others?
>      
>      John Darrington <address@hidden> writes:
>      
>      > My system fails the new test:
>      >
>      > 395. factor.at:1803: testing FACTOR /ROTATION=NOROTATE ...
>      > ../../tests/factor.at:1821: pspp -O format=csv factor-norotate.sps
>      > --- -   2012-04-04 11:18:24.388115600 +0100
>      > +++ 
> /home/Darringt/.p/P/UTP_00/ClearQuest/tests/testsuite.dir/at-groups/395/stdout
>       2012-04-04 11:18:23.366814100 +0100
>      > @@ -7,7 +7,7 @@
>      >  TRAIT5,7.29,2.66,7
>      >  
>      >  Table: KMO and Bartlett's Test
>      > -Kaiser-Meyer-Olkin Measure of Sampling Adequacy,,1.00
>      > +Kaiser-Meyer-Olkin Measure of Sampling Adequacy,,NaN
>      >  Bartlett's Test of Sphericity,Approx. Chi-Square,NaN
>      >  ,df,10
>      >  ,Sig.,NaN
>      > 395. factor.at:1803:  FAILED (factor.at:1821)
>      >
>      >
>      > On Tue, Apr 03, 2012 at 10:00:28PM -0700, Ben Pfaff wrote:
>      >      Thank you very much for the bug report.  I reproduced the bug and
>      >      fixed this on the PSPP "master" branch.
>      >      -- 
>      >      Ben Pfaff 
>      >      http://benpfaff.org
>      >      
>      >      _______________________________________________
>      >      Bug-gnu-pspp mailing list
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>      >      https://lists.gnu.org/mailman/listinfo/bug-gnu-pspp
>      
>      -- 
>      Ben Pfaff 
>      http://benpfaff.org

-- 
Ben Pfaff 
http://benpfaff.org