Date:         Thu, 19 Dec 2002 14:08:18 +1100
Reply-To:     rangarajan <b.rangarajan@pgrad.unimelb.edu.au>
Sender:       "SPSSX(r) Discussion" <SPSSX-L@LISTSERV.UGA.EDU>
From:         rangarajan <b.rangarajan@pgrad.unimelb.edu.au>
Subject:      WHY DIFFERENT n's
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Hi;
I ran the following syntax and i get two different valid N's . could
somebody explain why is it so. I am using the same formula in two syntax
but when i run frequency procedure at different stages the out put is
different.
syntax one:
SEL IF (I1110188 GT 100 AND I1110288 GT 100).
compute posteq87=(i1110288*100/100.1)/(d1110687**0.5).
COMPUTE PREG87=(I1110188*100/100.1)/(D1110687**0.5).
FREQUENCIES
  VARIABLES= preg87 posteq87 /FORMAT=NOTABLE
  /STATISTICS=MEAN MEDIAN.
SEL IF (I1110189 GT 100 AND I1110289 GT 100).
compute posteq88=(i1110289*100/101.4)/(d1110688**0.5).
COMPUTE PREG88=(I1110189*100/101.4)/(D1110688**0.5).
FREQUENCIES
  VARIABLES= preg88 posteq88 /FORMAT=NOTABLE
  /STATISTICS=MEAN MEDIAN.

Syntax two:
SEL IF (I1110188 GT 100 AND I1110288 GT 100).
compute posteq87=(i1110288*100/100.1)/(d1110687**0.5).
COMPUTE PREG87=(I1110188*100/100.1)/(D1110687**0.5).
SEL IF (I1110189 GT 100 AND I1110289 GT 100).
compute posteq88=(i1110289*100/101.4)/(d1110688**0.5).
COMPUTE PREG88=(I1110189*100/101.4)/(D1110688**0.5).
FREQUENCIES
  VARIABLES=PREG87 POSTEQ87
 PREG88 POSTEQ88
 /FORMAT=NOTABLE
  /STATISTICS=MEAN MEDIAN.

I hope somebody will be able to enlighten me why differences in the output.
Thanks in advance.
rangarajan