Date: Tue, 20 Jul 2010 13:36:02 -0400
Reply-To: Gene Maguin <firstname.lastname@example.org>
Sender: "SPSSX(r) Discussion" <SPSSX-L@LISTSERV.UGA.EDU>
From: Gene Maguin <email@example.com>
Subject: Re: three way interaction vs separate analysis with 2 way
Content-Type: text/plain; charset="us-ascii"
>>the dichot. moderator is gender, so i just split the sample and calculated
the 2 way interactions for men and women seperately.
>>my assumption was that if i for example get a sign. interaction for men
not for women, that i can claim that there is a gender difference.
Gene: You can claim it but as a reviewer I don't think I'd accept it. For
instance, suppose the two-way interaction coefficient was -.03 (se=.06) for
men and +.03 (se=.07) for women. Neither is significant and the signs are
different. I wouldn't believe that women and differ.
>>but as i understand you two, you both would recommend a three way
>>gene you wrote the following 'These two equation sets are apples and
oranges. The answer to what to do has nothing to do with statistics. The
correct answer is determined by the question you want an answer to. '
>>can you give an example when you would go for split sample with 2 way
interactions. thanks for your helpful input!
Gene: Not offhand. But, I'd bet that if you stated your hypothesis or
question, it would imply a three way interaction.
To manage your subscription to SPSSX-L, send a message to
LISTSERV@LISTSERV.UGA.EDU (not to SPSSX-L), with no body text except the
command. To leave the list, send the command
For a list of commands to manage subscriptions, send the command