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A functional mixed model for scalar on function regression with application to a functional MRI study.

ABSTRACT: Motivated by a functional magnetic resonance imaging (fMRI) study, we propose a new functional mixed model for scalar on function regression. The model extends the standard scalar on function regression for repeated outcomes by incorporating subject-specific random functional effects. Using functional principal component analysis, the new model can be reformulated as a mixed effects model and thus easily fit. A test is also proposed to assess the existence of the subject-specific random functional effects. We evaluate the performance of the model and test via a simulation study, as well as on data from the motivating fMRI study of thermal pain. The data application indicates significant subject-specific effects of the human brain hemodynamics related to pain and provides insights on how the effects might differ across subjects.

SUBMITTER: Ma W

PROVIDER: S-EPMC8286587 | biostudies-literature | 2021 Jul

REPOSITORIES: biostudies-literature

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A functional mixed model for scalar on function regression with application to a functional MRI study.

Ma Wanying W Xiao Luo L Liu Bowen B Lindquist Martin A MA

Biostatistics (Oxford, England) 20210701 3

Motivated by a functional magnetic resonance imaging (fMRI) study, we propose a new functional mixed model for scalar on function regression. The model extends the standard scalar on function regression for repeated outcomes by incorporating subject-specific random functional effects. Using functional principal component analysis, the new model can be reformulated as a mixed effects model and thus easily fit. A test is also proposed to assess the existence of the subject-specific random function ...[more]

PMID: 31631222

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Dataset Information

A functional mixed model for scalar on function regression with application to a functional MRI study.

Publications

A functional mixed model for scalar on function regression with application to a functional MRI study.

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