MULTIPLE REGRESSION ANALYSIS OF THE OCCUPATIONAL STATUS OF TWINS: A COMPARISON OF ECONOMIC AND BEHAVIOURAL GENETICS MODELS
比较了DeFries-Fulker模型与传统固定效应模型在双胞胎数据上的表现，发现教育对澳大利亚职业地位的影响在控制遗传和共享环境因素后，与未控制时的估计值相近，遗传和共享环境因素对教育回报的贡献最多仅1-2个百分点。
ABSTRACT The purpose of this note is to compare the performance of the model of DeFries and Fulker [hereafter ‘the DFF model’] with the conventional fixed effects model in the analysis of data on twins in the study of economic well‐being. Unlike the fixed‐effects model that has traditionally been estimated in the economics literature, the DFF model provides explicit controls for genetic and shared environmental factors. The weight of the evidence from estimation of the two models considered is that the impact of education in Australia, holding constant genetic and shared environmental factors, is of the same order of magnitude as that estimated in studies that do not take account of these factors: at most ability and shared environmental factors contribute 1 to 2 percentage points to the gross return to education. The similarity of the results computed for the different models employed is reassuring, and suggests that reliable controls for the omitted genetic and shared environment variables are obtained through these indirect methods.