Kernel-based covariate functional balancing for observational studies.
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ABSTRACT:
SUBMITTER: Wong RKW
PROVIDER: S-EPMC5976457 | biostudies-literature | 2018 Mar
REPOSITORIES: biostudies-literature
Publications
Kernel-based covariate functional balancing for observational studies.
Wong Raymond K W RKW Chan Kwun Chuen Gary KCG
Biometrika 20171208 1
Covariate balance is often advocated for objective causal inference since it mimics randomization in observational data. Unlike methods that balance specific moments of covariates, our proposal attains uniform approximate balance for covariate functions in a reproducing-kernel Hilbert space. The corresponding infinite-dimensional optimization problem is shown to have a finite-dimensional representation in terms of an eigenvalue optimization problem. Large-sample results are studied, and numerica ...[more]
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