James W H
Acta Genet Med Gemellol (Roma). 1979;28(1):69-71. doi: 10.1017/s0001566000009363.
Weinberg's differential method, whereby the frequency of dizygotic twins in a population is obtained by doubling the number of opposite-sexed pairs, might not be valid. Data are presented indicating a higher frequency of same-sexed than opposite-sexed pairs among samples of dizygotic twins ascertained at birth, thus favoring the hypothesis that, contrary to the method's fundamental assumption, the sexes of the two twin zygotes be not independent.
温伯格差分法通过将异性双胞胎对数加倍来得出人群中异卵双胞胎的频率，该方法可能并不有效。所呈现的数据表明，在出生时确定的异卵双胞胎样本中，同性双胞胎对数高于异性双胞胎对数，因此支持了这样一种假设，即与该方法的基本假设相反，两个异卵合子的性别并非相互独立。
