Figure 1: The projections for the pendigit data onto the estimated first
two-dimensional subspace. The colors represent the ten classes. The 200
reduced features are used by stratified random subset for performing KPCA
and KSIR with Gaussian kernel of scale 0.05.
Wu, H. M.* (2008). Kernel Sliced Inverse
Regression with Applications to Classification, Journal of
Computational and Graphical Statistics. 17(3), 590-610.