Kanninen Ohto, Karhula Aleksi
Labour Institute for Economic Research, Helsinki, Finland.
Department of Social Research, University of Turku, Turku, Finland.
PLoS One. 2016 Jul 20;11(7):e0158943. doi: 10.1371/journal.pone.0158943. eCollection 2016.
The human sex ratio at birth (SRB) is approximately 107 boys for every 100 girls. SRB was rising until the World War II and has been declining slightly after the 1950s in several industrial countries. Recent studies have shown that SRB varies according to exposure to disasters and socioeconomic conditions. However, it remains unknown whether changes in SRB can be explained by observable macro-level socioeconomic variables across multiple years and countries. Here we show that changes in disposable income at the macro level positively predict SRB in OECD countries. A one standard deviation increase in the change of disposable income is associated with an increase of 1.03 male births per 1000 female births. The relationship is possibly nonlinear and driven by extreme changes. The association varies from country to country being particular strong in Estonia. This is the first evidence to show that economic and social conditions are connected to SRB across countries at the macro level. This calls for further research on the effects of societal conditions on general characteristics at birth.
人类出生时的性别比（SRB）约为每100名女孩对应107名男孩。在第二次世界大战之前，性别比一直在上升，而在20世纪50年代之后，一些工业化国家的性别比略有下降。最近的研究表明，性别比会因灾害暴露和社会经济状况而有所不同。然而，性别比的变化是否可以通过多年来多个国家可观察到的宏观层面社会经济变量来解释，这一点仍然未知。在此我们表明，经合组织国家中宏观层面可支配收入的变化正向预测性别比。可支配收入变化每增加一个标准差，每1000例女性出生中男性出生数就会增加1.03例。这种关系可能是非线性的，并且由极端变化驱动。这种关联因国家而异，在爱沙尼亚尤为显著。这是首个表明宏观层面各国经济和社会状况与性别比相关的证据。这就需要进一步研究社会状况对出生时一般特征的影响。
