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Re: st: ROC question:  STATA vs SPSS
From 
 
Richard Williams <[email protected]> 
To 
 
[email protected],        "[email protected]" <[email protected]> 
Subject 
 
Re: st: ROC question:  STATA vs SPSS 
Date 
 
Thu, 28 Jul 2011 16:16:23 -0500 
At 02:53 PM 7/28/2011, Danielle Boyce wrote:
Hi,
I usually use STATA for my data analysis, but for various reasons, 
ran one in SPSS first.  It gave me a negative cutoff point when my 
data have no negative values.  I re-ran in STATA and got the same 
AUC, but no negative cutoff, and everything else (CIs, cutoffs) are 
ever-so-slightly off compared to SPSS.
I'm just wondering if anyone knows why this discrepancy exists.
Thanks!
Danielle
I don't know specifically about ROC, but often such differences are 
due to differences in parameterization. One program might do 0 versus 
1 while another does 1 versus 0. Or, one program adds a constant 
while another subtracts a cutpoint. If possible, try to compare how 
the two programs are parameterizing things.
-------------------------------------------
Richard Williams, Notre Dame Dept of Sociology
OFFICE: (574)631-6668, (574)631-6463
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EMAIL:  [email protected]
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