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Re: Sign on regression coef?

Posted by William B. Ware on Jan 03, 2007; 2:30am
URL: http://spssx-discussion.165.s1.nabble.com/Sign-on-regression-coef-tp1072952p1072958.html

Lisa,

Look at the correlation between the two IVs.  I'm going to guess that it
is pretty large... I think that what you have is a case of "suppression."
Check out one of the older editions of Cohen and Cohen or Cohen, Cohen,
Aiken, and West for an explanation...

wbw

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William B. Ware, Professor                         Educational Psychology,
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On Tue, 2 Jan 2007, Lisa Stickney wrote:

> Hi SPSSers,
>
>    First off, Happy New Year to all.  Next, my apologies for posting a stats question & not an SPSS question, but I'm hoping someone can help me.  I have 3 variables: 2 independent & 1 dependent.  When I look at the correlation table, they all correlate positively with each other.  However, when I put them in a regression, the regression coefficient on one of the independent variables becomes negative.  Can anyone tell me when/why this might occur?  Thanks in advance.
>
>    Best,
>        Lisa
>
> Lisa T. Stickney
> Ph.D. Candidate
> The Fox School of Business
>     and Management
> Temple University
> [hidden email]
>