The 11th KMGS will be held on September 29th, Thursday, at Natural Science Building (E6-1) Room 1501.
We invite a speaker Junyoung Park (박준영) from the Dept. of Mathematical Sciences, KAIST.
The abstract of the talk is as follows.
Slot (AM 11:50~PM 12:30)
[Speaker] Junyoung Park (박준영) from Dept. of Mathematical Sciences, KAIST, supervised by Prof. Cheolwoo Park (박철우 교수님), Prof. Jeongyoun Ahn (안정연 교수님)
[Title] Kernel methods for radial transformed compositional data with many zeros
[Discipline] Statistics
[Abstract]
Compositional data analysis with a high proportion of zeros has gained increasing popularity, especially in chemometrics and human gut microbiomes research. Statistical analyses of this type of data are typically carried out via a log-ratio transformation after replacing zeros with small positive values. We should note, however, that this procedure is geometrically improper, as it causes anomalous distortions through the transformation. We propose a radial transformation that does not require zero substitutions and more importantly results in essential equivalence between domains before and after the transformation. We show that a rich class of kernels on hyperspheres can successfully define a kernel embedding for compositional data based on this equivalence. The applicability of the proposed approach is demonstrated with kernel principal component analysis.
[Language] Korean (English if it is requested)