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http://dx.doi.org/10.7465/jkdi.2014.25.5.1069

Functional clustering for clubfoot data: A case study  

Lee, Miae (Credit Planning Team, Lotte Card)
Lim, Johan (Department of Statistics, Seoul National University)
Park, Chungun (Department of Mathematics, Kyonggi University)
Lee, Kyeong Eun (Department of Statistics, Kyungpook National University)
Publication Information
Journal of the Korean Data and Information Science Society / v.25, no.5, 2014 , pp. 1069-1077 More about this Journal
Abstract
A clubfoot is a kind of congenital deformity of foot, which is internally rotated at the ankle. In this paper, we are going to cluster the curves of relative differences between regular and operated feet. Since these curves are irregular and sparsely sampled, general clustering models could not be applied. So the clustering model for sparsely sampled functional data by James and Sugar (2003) are applied and parameters are estimated using EM algorithm. The number of clusters is determined by the distortion function (Sugar and James, 2003) and two clusters of the curves are found.
Keywords
Club foot; clustering; model-based clustering; sparse functional data;
Citations & Related Records
Times Cited By KSCI : 1  (Citation Analysis)
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