Abstract:
:In this article, we investigate clustering methods for multilevel functional data, which consist of repeated random functions observed for a large number of units (e.g., genes) at multiple subunits (e.g., bacteria types). To describe the within- and between variability induced by the hierarchical structure in the data, we take a multilevel functional principal component analysis (MFPCA) approach. We develop and compare a hard clustering method applied to the scores derived from the MFPCA and a soft clustering method using an MFPCA decomposition. In a simulation study, we assess the estimation accuracy of the clustering membership and the cluster patterns under a series of settings: small versus moderate number of time points; various noise levels; and varying number of subunits per unit. We demonstrate the applicability of the clustering analysis to a real data set consisting of expression profiles from genes activated by immunity system cells. Prevalent response patterns are identified by clustering the expression profiles using our multilevel clustering analysis.
journal_name
Biometricsjournal_title
Biometricsauthors
Serban N,Jiang Hdoi
10.1111/j.1541-0420.2011.01714.xsubject
Has Abstractpub_date
2012-09-01 00:00:00pages
805-14issue
3eissn
0006-341Xissn
1541-0420journal_volume
68pub_type
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