Statistical Science

Causal Inference: A Missing Data Perspective

Peng Ding and Fan Li

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Abstract

Inferring causal effects of treatments is a central goal in many disciplines. The potential outcomes framework is a main statistical approach to causal inference, in which a causal effect is defined as a comparison of the potential outcomes of the same units under different treatment conditions. Because for each unit at most one of the potential outcomes is observed and the rest are missing, causal inference is inherently a missing data problem. Indeed, there is a close analogy in the terminology and the inferential framework between causal inference and missing data. Despite the intrinsic connection between the two subjects, statistical analyses of causal inference and missing data also have marked differences in aims, settings and methods. This article provides a systematic review of causal inference from the missing data perspective. Focusing on ignorable treatment assignment mechanisms, we discuss a wide range of causal inference methods that have analogues in missing data analysis, such as imputation, inverse probability weighting and doubly robust methods. Under each of the three modes of inference—Frequentist, Bayesian and Fisherian randomization—we present the general structure of inference for both finite-sample and super-population estimands, and illustrate via specific examples. We identify open questions to motivate more research to bridge the two fields.

Article information

Source
Statist. Sci., Volume 33, Number 2 (2018), 214-237.

Dates
First available in Project Euclid: 3 May 2018

Permanent link to this document
https://projecteuclid.org/euclid.ss/1525313143

Digital Object Identifier
doi:10.1214/18-STS645

Mathematical Reviews number (MathSciNet)
MR3797711

Zentralblatt MATH identifier
1397.62125

Keywords
Assignment mechanism ignorability imputation missing data mechanism observational studies potential outcome propensity score randomization weighting

Citation

Ding, Peng; Li, Fan. Causal Inference: A Missing Data Perspective. Statist. Sci. 33 (2018), no. 2, 214--237. doi:10.1214/18-STS645. https://projecteuclid.org/euclid.ss/1525313143


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