are the same as that of plot (a). \[experiment:gauss\]](./eps/graph_gauss1.pdf "fig:") (a) sphere-like gaussian. comparison with existing methods.

![Top-10 NN retrieval results for 128-dimensional gaussian data. PRH(m, n, $\lambda$) indicates the proposed method with $m$-times basic isotropic rotation, $n$-times basic PCA rotation, and PCAT parameter $\lambda$ (Eq. (\[eq:pca\_rotation\])). Upper row is for the data with log-variance value of one. Lower row is for the data with log-variance of three (described in Section \[sec:toydata\_experiment\]). Abbreviated legends of plot (d) are the same as that of plot (a). \[experiment:gauss\]](./eps/graph_gauss1_lambdas.pdf "fig:") (b) sphere-like gaussian. effect of PCAT. $\qquad \qquad \qquad$

![Top-10 NN retrieval results for 128-dimensional gaussian data. PRH(m, n, $\lambda$) indicates the proposed method with $m$-times basic isotropic rotation, $n$-times basic PCA rotation, and PCAT parameter $\lambda$ (Eq. (\[eq:pca\_rotation\])). Upper row is for the data with log-variance value of one. Lower row is for the data with log-variance of three (described in Section \[sec:toydata\_experiment\]). Abbreviated legends of plot (d) are the same as that of plot (a). \[experiment:gauss\]](./eps/graph_gauss1_rpcas.pdf "fig:") (c) sphere-like gaussian. effect of RSPCA. $\qquad \qquad \qquad$

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![Top-10 NN retrieval results for 128-dimensional gaussian data. PRH(m, n, $\lambda$) indicates the proposed method with $m$-times basic isotropic rotation, $n$-times basic PCA rotation, 