AI 中文总结
研究利用英国生物银行中基因遗传的准随机变化，估计教育多基因指数对教育和收入的因果效应，并用因果中介框架将其总遗传收入效应分解为间接和直接效应，还通过敏感性分析处理不确定性，揭示多数效应通过教育年限起作用。
AI 中文摘要
与教育成就相关的基因能因果性地提高劳动力市场收入，但这种关系背后的经济机制尚不清楚。利用英国生物银行中兄弟姐妹间基因遗传的准随机变化，估计教育多基因指数（Ed PGI）对教育和收入的因果效应。Ed PGI增加一个标准差会使受教育年限提高0.5年，后期收入提高约5%。然后使用因果中介框架将总遗传收入效应分解为通过教育年限起作用的间接渠道和剩余的直接效应。与基于结构模型的分解不同，此方法基于设计；通过敏感性分析透明地处理一个不确定性来源（多一年教育的因果回报）。在约6%的相关教育回报下，65%至75%的总遗传收入效应通过教育年限渠道起作用。英国经济学文献的准实验估计表明教育回报更高，这意味着中介份额更大，Ed PGI的大部分收入效应通过完成的教育年限起作用。
英文摘要
Genes associated with educational attainment causally improve labour market income, but the economic mechanism behind this relationship is not clear. Using quasi-random variation in genetic inheritance across siblings in the UK Biobank, I estimate the causal effect of the Education PolyGenic Index (Ed PGI) on education and income. A one standard deviation increase in the Ed PGI raises completed education by 0.5 years and later-life income by around 5 percent (replicating the main estimates in Carvalho 2025). I then decompose this total genetic income effect into an indirect channel operating through education years and a residual direct effect, using a causal mediation framework. Unlike structural model-based decompositions, this approach is design-based; one remaining source of uncertainty (the causal return to an extra year of education) is handled transparently through a sensitivity analysis. At correlational education returns of around 6 percent, 65 to 75 percent of the total genetic income effect operates through the years of education channel. Quasi-experimental estimates from the economics literature for Britain imply higher returns to education, suggesting that the mediated share is larger and that the majority of the Ed PGI's income effect operates through completed years of education.
CommentsMain text: 39 pages, 10 figures. Supplementary appendix: 9 pages, 3 figures
