Abstract
In this research note, DeFries-Fulker (DF) regression analysis is reframed in model-fitting terms, where an individual's expected score is modeled as a function of their co-twin's proband status. This more flexible implementation of the DF model allows DZ-O twins to be incorporated in a sex-limitation model. Brief simulation results are presented along with the Mx scripts used.
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References
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Purcell, S., Sham, P.C. A Model-Fitting Implementation of the DeFries-Fulker Model for Selected Twin Data. Behav Genet 33, 271–278 (2003). https://doi.org/10.1023/A:1023494408079
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DOI: https://doi.org/10.1023/A:1023494408079