Graffelman J, Hoekstra R F
Department of Economics, University Pompeu Fabra, Ramon Trias Fargas, Barcelona, Spain.
Hum Biol. 2000 Jun;72(3):433-45.
Many factors have been hypothesized to affect the human secondary sex ratio (the annual percentage of males among all live births), among them race, parental ages, and birth order. Some authors have even proposed warfare as a factor influencing live birth sex ratios. The hypothesis that during and shortly after periods of war the human secondary sex ratio is higher has received little statistical treatment. In this paper we evaluate the war hypothesis using 3 statistical methods: linear regression, randomization, and time-series analysis. Live birth data from 10 different countries were included. Although we cannot speak of a general phenomenon, statistical evidence for an association between warfare and live birth sex ratio was found for several countries. Regression and randomization test results were in agreement. Time-series analysis showed that most human sex-ratio time series can be described by a common model. The results obtained using intervention models differed somewhat from results obtained by regression methods.
许多因素被假定会影响人类的出生性别比（所有活产婴儿中男性的年度百分比），其中包括种族、父母年龄和出生顺序。一些作者甚至提出战争是影响活产性别比的一个因素。关于在战争期间及战争刚结束后人类出生性别比更高这一假说，几乎没有得到统计学处理。在本文中，我们使用三种统计方法评估战争假说：线性回归、随机化和时间序列分析。纳入了来自10个不同国家的活产数据。虽然我们不能说这是一个普遍现象，但在几个国家发现了战争与活产性别比之间存在关联的统计证据。回归和随机化测试结果一致。时间序列分析表明，大多数人类性别比时间序列可以用一个通用模型来描述。使用干预模型获得的结果与通过回归方法获得的结果略有不同。
