"::::: mikemikev, that's just not correct.  'genetic regression' is the statistical idea of regression towards the mean applied to genetics (considered as a random phenomenon).  the reason why siblings' scores are closer to the mean (according to Jensen) is that when taking a random sampling of genes from the same pair of parents, the second draw (e.g. second child) will on average be less extreme than the first child (given a list of assumptions too long to mention at this point).  Ludwigs2 

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