Covariate balancing for high-dimensional samples in controlled experiments

In controlled experiments, achieving covariate balancing across all groups is crucial as it ensures that the estimated treatment effects are not confounded by the effects of covariates. This study proposes a mixed-integer nonlinear programming model to address the covariate balancing problem. Specif...

Full description

Bibliographic Details
Main Authors: Luo, Xi, Yan, Penggao, Yan, Ran, Wang, Shuaian
Other Authors: School of Civil and Environmental Engineering
Format: Journal Article
Language:English
Published: 2025
Subjects:
Online Access:https://hdl.handle.net/10356/182520
_version_ 1824457029899517952
author Luo, Xi
Yan, Penggao
Yan, Ran
Wang, Shuaian
author2 School of Civil and Environmental Engineering
author_facet School of Civil and Environmental Engineering
Luo, Xi
Yan, Penggao
Yan, Ran
Wang, Shuaian
author_sort Luo, Xi
collection NTU
description In controlled experiments, achieving covariate balancing across all groups is crucial as it ensures that the estimated treatment effects are not confounded by the effects of covariates. This study proposes a mixed-integer nonlinear programming model to address the covariate balancing problem. Specifically, we introduce a new covariate imbalance measure, which is the maximum discrepancy in both the first and second central moments between any two groups. The second central moment can effectively capture the correlation of covariates in a physical sense, which is crucial for partitioning high-dimensional samples. A mixed-integer nonlinear programming model is constructed to minimize the proposed measure to obtain the optimal partitioning results. The nonlinear model is then linearized to accelerate the optimization process. We conduct computational experiments based on simulated datasets, including one-dimensional, two-dimensional, and three-dimensional Gaussian distributed samples, and a real clinic trial dataset. Compared to the conventional discrepancy-based method, our method achieves a 54.81% and a 40.6% reduction in the maximum discrepancy of partitioning results in the two-dimensional simulated Gaussian samples and the real clinic trial dataset, respectively. These results demonstrate the superiority of the proposed model in partitioning high-dimensional samples with correlated covariates compared with the conventional discrepancy-based method.
first_indexed 2025-02-19T04:03:30Z
format Journal Article
id ntu-10356/182520
institution Nanyang Technological University
language English
last_indexed 2025-02-19T04:03:30Z
publishDate 2025
record_format dspace
spelling ntu-10356/1825202025-02-05T08:00:10Z Covariate balancing for high-dimensional samples in controlled experiments Luo, Xi Yan, Penggao Yan, Ran Wang, Shuaian School of Civil and Environmental Engineering Engineering Covariate balance Partitioning problem In controlled experiments, achieving covariate balancing across all groups is crucial as it ensures that the estimated treatment effects are not confounded by the effects of covariates. This study proposes a mixed-integer nonlinear programming model to address the covariate balancing problem. Specifically, we introduce a new covariate imbalance measure, which is the maximum discrepancy in both the first and second central moments between any two groups. The second central moment can effectively capture the correlation of covariates in a physical sense, which is crucial for partitioning high-dimensional samples. A mixed-integer nonlinear programming model is constructed to minimize the proposed measure to obtain the optimal partitioning results. The nonlinear model is then linearized to accelerate the optimization process. We conduct computational experiments based on simulated datasets, including one-dimensional, two-dimensional, and three-dimensional Gaussian distributed samples, and a real clinic trial dataset. Compared to the conventional discrepancy-based method, our method achieves a 54.81% and a 40.6% reduction in the maximum discrepancy of partitioning results in the two-dimensional simulated Gaussian samples and the real clinic trial dataset, respectively. These results demonstrate the superiority of the proposed model in partitioning high-dimensional samples with correlated covariates compared with the conventional discrepancy-based method. 2025-02-05T08:00:10Z 2025-02-05T08:00:10Z 2024 Journal Article Luo, X., Yan, P., Yan, R. & Wang, S. (2024). Covariate balancing for high-dimensional samples in controlled experiments. Journal of the Operational Research Society, 2423362-. https://dx.doi.org/10.1080/01605682.2024.2423362 0160-5682 https://hdl.handle.net/10356/182520 10.1080/01605682.2024.2423362 2-s2.0-85208470061 2423362 en Journal of the Operational Research Society © 2024 The Operational Research Society. All rights reserved.
spellingShingle Engineering
Covariate balance
Partitioning problem
Luo, Xi
Yan, Penggao
Yan, Ran
Wang, Shuaian
Covariate balancing for high-dimensional samples in controlled experiments
title Covariate balancing for high-dimensional samples in controlled experiments
title_full Covariate balancing for high-dimensional samples in controlled experiments
title_fullStr Covariate balancing for high-dimensional samples in controlled experiments
title_full_unstemmed Covariate balancing for high-dimensional samples in controlled experiments
title_short Covariate balancing for high-dimensional samples in controlled experiments
title_sort covariate balancing for high dimensional samples in controlled experiments
topic Engineering
Covariate balance
Partitioning problem
url https://hdl.handle.net/10356/182520
work_keys_str_mv AT luoxi covariatebalancingforhighdimensionalsamplesincontrolledexperiments
AT yanpenggao covariatebalancingforhighdimensionalsamplesincontrolledexperiments
AT yanran covariatebalancingforhighdimensionalsamplesincontrolledexperiments
AT wangshuaian covariatebalancingforhighdimensionalsamplesincontrolledexperiments