Re: st: RRR with CI from logit model

[Michael Ingre <Michael.Ingre@ipm.ki.se>]

A follow up on statistical power.

I have calculated a few RRRs and an interesting pattern is emerging. 
Extreme comparisons give insignificant p-values but others don't.

RRR for 9.5 vs 1, p=.669
RRR for 9.5 vs 9, p=.030
RRR for  2  vs 1, p=.049

Predicted absolute probabilities are: 9.5=.33 , 9=.14, 2=.000020 & 
1=.000015

What is going on here? Am I doing something wrong? I appreciate any 
suggestion because this makes no sense to me.


Michael


> nlcom exp(81 * squared + 9 * linear + constant) /              ///
>          (1 + exp(81 * squared + 9 * linear + constant)) /    ///
>       exp(4 * squared + 2 * linear + constant) /            ///
> 	     (1 + exp(4 * squared + 2 * linear + constant))



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