Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin...

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Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zha ng Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang, Xingxing Xu, & Wen jie Li

Transcript of Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin...

Page 1: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Non-linear Dimensionality Reduction by Locally Linear Inlaying

Presented by Peng Zhang

Tianjin University, China

Yuexian Hou, Peng Zhang, Xiaowei Zhang, Xingxing Xu, & Wenjie Li

Page 2: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Why Nonlinear Methods

Inherent dimensionalities != the linear transformation of initial features Face image Example:

Figures from ISOMAP paper

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Page 3: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Manifold Learning Local Linearity Global Embedding

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Page 4: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

A Run of ISOMAP

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PCA ISOMAPOriginal

Page 5: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Another Run of ISOMAP

Figures from ISOMAP paper

Page 6: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Other classical NLDR methods

LLE LTSA LLC Laplacian Eigenmaps LPP ……

Page 7: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Drawbacks of these methods

Most of these methods

at least quadratic time in N

fails on non-uniform dataset.

not robust to heterogeneous noise

Page 8: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Locally Linear Inlaying (LLI)

Linear time cost

Perform well on nonconvex samples

robust to heterogeneous noise

Page 9: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

1. Running time comparison

Page 10: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

2. Non-convex Swiss Roll Dataset

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Page 11: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

3. Swiss roll with heterogeneous noise

Isomap

LTSA LLC LLI

Original 2-D projection

Page 12: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

4. “Frey Face” dataset

Intensity of Illumination

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Page 13: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

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Page 14: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Connections to IR LLI in text background?

Positive Linearity in local area is better than global data Obtain local document sets (clusters or subtopics)

Reasons for Negative Different metric in text and image Image have natural manifold meaning

LLI in Renaissance Project? Local context basis Global context-sensitive embedding

Page 15: Non-linear Dimensionality Reduction by Locally Linear Inlaying Presented by Peng Zhang Tianjin University, China Yuexian Hou, Peng Zhang, Xiaowei Zhang,

Thank You!

Any Question???