in which summation is over selected category j and age l contributing to pth selection path, Graphicis the variance of selected parents of pth path, csjlp is the contribution of category sjl to that pth selection path, and Graphicand μsjl are, as defined previously, the variance and genetic superiority of the selected group sjl, in generation t, respectively. Hence, the genetic variances in newborns of the subsequent generation are the assembled genetic variances of selected parents and Mendelian-sampling variance: