search for: dizygot

...ariable---zygosity. Dependent variables are all parental (mom, dad separately of course) psychiatric diagnoses. In my data, twin pair ID is the clustering variable; correlations are expected to be exchangeable but substantially different between members of monozygotic twin pairs and members of dizygotic twin pairs. Hence, in my analyses, the variable that's "outer" to twin pair is monozygotic vs. dizygotic which of course applies to the whole pair. nlme() does all that but requires quasi-continuous responses, according to the preface/intro of P&B's mixed models book an...

Hi all, I have a set of 3D statistical parametric maps derived from an fMRI experiment in which we have two levels of dependency. - All subjects were scanned twice. - All subject are dizygotic (non-identical) twins. For every single scan (and thus statical map) we have a behavioural measure, which we would like to regress against the set of maps, while correcting for the dependency between scans and ideally also between twins. In neuroimaging software like SPM and FSL it is not poss...