Re: contrast (orthogonal) coding with unequal cell frequencies

Posted by Sidra on Oct 20, 2016; 1:58am
URL: http://spssx-discussion.165.s1.nabble.com/contrast-orthogonal-coding-with-unequal-cell-frequencies-tp5733307p5733323.html

I have another query.

As I'm working through my analysis using contrast variables, I am presented with this new problem. I want to control for the confounding effect of potential confounders using 10% rule to see the adjusted effect of main predictor on outcome. The two contrast categories that were created using "contrast orthogonal coding"  were supposed to represent two variables; marital status and childbearing status. I want to see whether the aforementioned two variables are confounders. Now I'm not sure whether I have to enter both contrast variables simultaneously with main predictor in the model to see the confounding effect of marital status and childbearing status  or I can enter them separately into the model (what I was supposed to do , had I worked with original variables) to see how much change each individual variable brings in the coefficient of main predictor.

Kindly help me on this.