Manifold Dimension Estimation via Local Graph Structure
Summary
A new framework for manifold dimension estimation, integrating Principal Component Analysis (PCA) with regression techniques, is introduced to effectively capture a manifold's local graph structure. This approach explicitly models underlying curvature, moving beyond the traditional flatness assumption. Two representative estimators, Quadratic Embedding (QE) and Total Least Squares (TLS), are detailed. QE uses ordinary least squares with an F-statistic for model evaluation, while TLS employs total least squares, assessing fit via relative drops in total error. Experiments on 18 synthetic datasets (with n=500 and n=2000 samples, both noiseless and noisy) and 6 additional nonlinearly embedded manifolds demonstrate that QE and TLS perform competitively with, and often outperform, state-of-the-art methods like Local PCA, CA-PCA, TwoNN, and DanCo. Their advantages are particularly evident with small sample sizes, nonlinear embeddings, and noisy data. Real-world evaluations on ISOMAP (698 images, 3D), MNIST (6,742 images, 8-11D), and ISOLET (6,240 vectors, 16-22D) datasets further confirm their robustness and accuracy, especially where ambient dimensions significantly exceed intrinsic dimensions.
Key takeaway
For research scientists or AI practitioners working with high-dimensional data, consider Quadratic Embedding (QE) or Total Least Squares (TLS) for intrinsic dimension estimation. These methods excel with noisy data, small sample sizes, and nonlinearly embedded manifolds, offering superior accuracy over traditional flatness-assumption techniques. You should prioritize these curvature-aware approaches when existing estimators struggle with complex data geometries or high ambient dimensions.
Key insights
Integrating PCA with regression captures local graph structure for robust manifold dimension estimation.
Principles
- Explicitly model manifold curvature via local graph functions.
- Regression-based fitting enhances estimation stability.
- Robustness to noise and varying neighborhood sizes is crucial.
Method
The framework applies local PCA to neighborhoods, then fits quadratic regression models (OLS for QE, TLS for TLS) to PCA coordinates, evaluating fit via F-statistics or relative error drops to determine intrinsic dimension.
In practice
- Use QE/TLS for noisy, nonlinearly embedded data.
- Prioritize curvature-aware methods for complex manifolds.
- Consider QE for smaller sample sizes.
Topics
- Manifold Dimension Estimation
- Local Graph Structure
- Principal Component Analysis
- Quadratic Embedding
- Total Least Squares
- Nonlinear Embeddings
Code references
Best for: AI Scientist, Research Scientist
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Editorial summary, takeaway, and curation by AIssential. Original article published by stat.ML updates on arXiv.org.