Gray E, Hurt V K, Oyewole S O
J Hered. 1983 May-Jun;74(3):204-6. doi: 10.1093/oxfordjournals.jhered.a109767.
During 1981, sex ratio data and preferences for family size and for combinations and permutations of children were provided by 333 Nigerian students at the University of Ilorin, Ilorin, Nigeria. For the present and parental generations combined, the secondary sex ratio was estimated to be 95.8 males:100 females. In the projected families, preferences for family sizes resulted in an average of 4.88 children per family. The most preferred family consisted of four children--a 2m2f combination in a mfmf order, whereas the second most preferred family consisted of five children--3m2f combination in a mfmfm order. Also expressed was a strong preference for permutations of sexes, resulting in a male child as first-born followed by an alternation of sexes. A greater preference for male children was indicated by the combined sex ratio of 167 males:100 females for the preferred families.
1981年期间，尼日利亚伊洛林大学的333名尼日利亚学生提供了性别比数据以及对家庭规模、子女组合和排列的偏好。将当前一代和父母一代合并计算，二胎性别比估计为每100名女性对应95.8名男性。在预计组建的家庭中，对家庭规模的偏好导致每个家庭平均有4.88个孩子。最受欢迎的家庭由四个孩子组成——按mfmf顺序排列的2男2女组合，而第二受欢迎的家庭由五个孩子组成——按mfmfm顺序排列的3男2女组合。同时也表达了对性别排列的强烈偏好，即头胎为男孩，之后性别交替。受欢迎家庭的性别比为每100名女性对应167名男性，这表明对男孩的偏好更大。
