Hello list,
Date: Mon, 11 Jan 2010 13:49:52 +0100
Message-ID: <[email protected]>
From: [email protected]
To: undisclosed-recipients:;
I'm doing a SNP analysis using the xi:logistic function.
To exclude possible confounder, I'm adjusting my calculations for different variables, e.g. sex and ethnics.
My study population consists of 4 different ethnicities, coded as 1 2 3 4. sex is coded 1 2. SNPs are coded 1 2 3 (e.g. CC/CT/TT).
I don't understand the following:
When I calculate:
xi:logistic i.snp sex ethnics
i get different results to
xi:logistic i.snp sex i.ethnics
Why is that, and what is the correct way to adjust for ethnics, using i.ethnics or just ethnics?
Thank you,
Kristina
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