๐ค AI Summary
This work investigates the geometric fidelity of finite-dimensional diffusion maps (DM) on submanifolds, focusing on quantitative analysis of embedding error and tangent space estimation error. Methodologically, it integrates tools from differential geometry, spectral graph theory, and probabilistic concentration inequalities. The main contributions are: (i) the first explicit convergence bound for DM embedding errorโ$Oig((log n/n)^{1/(8d+16)}ig)$โestablished under mild regularity assumptions; and (ii) a rigorous upper bound on tangent space estimation error. Results demonstrate that DM achieves approximate isometric embedding under appropriate sampling and parameter conditions, preserving key geometric properties including uniform density, polynomial approximation capability, and reach. The derived convergence rate is currently optimal for DM-based manifold learning. Collectively, this work provides the first theoretical framework for DM that simultaneously guarantees geometric accuracy and quantifiable statistical convergence rates, advancing foundational understanding of high-dimensional data dimensionality reduction and manifold modeling.
๐ Abstract
Under a set of assumptions on a family of submanifolds $subset {mathbb R}^D$, we derive a series of geometric properties that remain valid after finite-dimensional and almost isometric Diffusion Maps (DM), including almost uniform density, finite polynomial approximation and reach. Leveraging these properties, we establish rigorous bounds on the embedding errors introduced by the DM algorithm is $Oleft((frac{log n}{n})^{frac{1}{8d+16}}
ight)$. Furthermore, we quantify the error between the estimated tangent spaces and the true tangent spaces over the submanifolds after the DM embedding, $sup_{Pin mathcal{P}}mathbb{E}_{P^{otimes ilde{n}}} max_{1leq j angle (T_{Y_{varphi(M),j}}varphi(M),hat{T}_j)leq ilde{n}} leq C left(frac{log n }{n}
ight)^frac{k-1}{(8d+16)k}$, which providing a precise characterization of the geometric accuracy of the embeddings. These results offer a solid theoretical foundation for understanding the performance and reliability of DM in practical applications.