Regression-based causal inference with factorial experiments: estimands, model specifications and design-based properties
Regression-based causal inference with factorial experiments: estimands, model specifications and design-based properties
复制标题
基于回归的因果推理与阶乘实验:估计值、模型规范和基于设计的属性
DOI:
10.1093/biomet/asab051
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发表时间:
2021
期刊:
影响因子:
2.7
通讯作者:
Ding, Peng
中科院分区:
文献类型:
--
作者:
Zhao, Anqi;Ding, Peng
Factorial designs are widely used because of their ability to accommodate multiple factors simultaneously. Factor-based regression with main effects and some interactions is the dominant strategy for downstream analysis, delivering point estimators and standard errors simultaneously via one least-squares fit. Justification of these convenient estimators from the design-based perspective requires quantifying their sampling properties under the assignment mechanism while conditioning on the potential outcomes. To this end, we derive the sampling properties of the regression estimators under a wide range of specifications, and establish the appropriateness of the corresponding robust standard errors for Wald-type inference. The results help to clarify the causal interpretation of the coefficients in these factor-based regressions, and motivate the definition of general factorial effects to unify the definitions of factorial effects in various fields. We also quantify the bias-variance trade-off between the saturated and unsaturated regressions from the design-based perspective.