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CPS1876 Sarbojit R. et al.
                     have  also  been  studied,  and  the  respective  misclassifiction  rates  are
                     reported as well
                         Table 1: Misclassification rates of different classifiers for   =  1000
                     Ex.   Bayes   NN-      NN-     GLMNET     RF     NN-    SVM-LIN   SVM-
                                  gMADD   ggMADD                      RAND              RBF
                     1   0.00(0.00)   0.00(0.00)   -   0.47(0.02)   0.01(0.01)   0.40(0.02)   0.37(0.02)   0.36(0.02)
                     2   0.00(0.00)   0.04(0.01)   -   0.47(0.02)   0.35(0.02)   0.50(0.02)   0.37(0.02)   0.38(0.02)
                     3   0.00(0.00)   0.44(0.02)   0.02(0.01)   0.48(0.02)   0.49(0.02)   0.50(0.02)   0.51(0.00)   0.47(0.00)
                     4   0.00(0.00)   0.48(0.02)   0.20(0.03)   0.47(0.01)   0.49(0.02)   0.49(0.02)   0.50(0.02)   0.49(0.02)

                         Clearly, one can observe that our proposed classifiers outperform the
                     rest for all the examples. Except random forest in Example 1, none of the
                     other  methods  get  even  close  to  the  proposed  classifiers.  In  some
                     examples,  the  average  misclassification  rates  of  the  other  classifiers  are
                     almost as bad as that of a classifier which assigns an observation randomly
                     to any one of the two classes.

                  5.  Concluding Remarks
                  In this article, we considered the nearest neighbor (NN) classifier in HDLSS
                  settings. We overcame the difficulty this classifier faces due to the use of the
                  Euclidean norm as a distance between two points. The Euclidean distance was
                  replaced  with  other  appropriately  constructed  dissimilarity  indices.  We
                  showed that even when the underlying populations are same in terms of their
                  location  and  scale  parameters,  the  proposed  classifier  showcases  perfect
                  classification as long as the components (or, groups of component variables)
                  have  different one-dimensional  marginal (or,  joint)  distributions  across  the
                  competing populations.

                  References
                  1.  Chan, Y.-B. and Hall, P. (2009). Scale adjustments for classifiers in high-
                      dimensional, low sample size settings. Biometrika, 96(2):469–478.
                  2.  Devroye, L., Gy¨orfi, L., and Lugosi, G. (2013). A Probabilistic Theory of
                      Pattern Recognition, volume 31. Springer Science & Business Media.
                  3.  Dutta, S. and Ghosh, A. K. (2016). On some transformations of high
                      dimension, low sample size data for nearest neighbor classification.
                      Machine Learning, 102(1):57–83.
                  4.  Hall, P., Marron, J. S., and Neeman, A. (2005). Geometric representation of
                      high dimension, low sample size data. Journal of the Royal Statistical
                      Society Series B, 67(3):427–444.
                  5.  Pal, A. K., Mondal, P. K., and Ghosh, A. K. (2016). High dimensional
                      nearest neighbor classification based on mean absolute differences of
                      inter-point distances. Pattern Recognition Letters, 74:1–8.



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