Joint estimation of smooth graph signals from partial linear measurements
- URL: http://arxiv.org/abs/2505.23240v2
- Date: Tue, 03 Jun 2025 07:19:05 GMT
- Title: Joint estimation of smooth graph signals from partial linear measurements
- Authors: Hemant Tyagi,
- Abstract summary: Weak consistency is established for certain choices of $G$ even when the individual $G_t$'s are very sparse and disconnected.<n>Results are extended to a multi-layer'' ranking problem where $x_t$ corresponds to the latent strengths of a collection of $n$ items.
- Score: 5.2395896768723045
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: Given an undirected and connected graph $G$ on $T$ vertices, suppose each vertex $t$ has a latent signal $x_t \in \mathbb{R}^n$ associated to it. Given partial linear measurements of the signals, for a potentially small subset of the vertices, our goal is to estimate $x_t$'s. Assuming that the signals are smooth w.r.t $G$, in the sense that the quadratic variation of the signals over the graph is small, we obtain non-asymptotic bounds on the mean squared error for jointly recovering $x_t$'s, for the smoothness penalized least squares estimator. In particular, this implies for certain choices of $G$ that this estimator is weakly consistent (as $T \rightarrow \infty$) under potentially very stringent sampling, where only one coordinate is measured per vertex for a vanishingly small fraction of the vertices. The results are extended to a ``multi-layer'' ranking problem where $x_t$ corresponds to the latent strengths of a collection of $n$ items, and noisy pairwise difference measurements are obtained at each ``layer'' $t$ via a measurement graph $G_t$. Weak consistency is established for certain choices of $G$ even when the individual $G_t$'s are very sparse and disconnected.
Related papers
- Optimal community detection in dense bipartite graphs [0.0]
We consider the problem of detecting a community of densely connected vertices in a high-dimensional bipartite graph of size $n_1 times n$.<n>We provide non-asymptotic upper and lower bounds on the smallest signal strength $delta*$ that is both necessary and sufficient to ensure the existence of a test with small enough type one and type two errors.<n>Our proposed tests involve a combination of hard-thresholded nonlinear statistics of the adjacency matrix, the analysis of which may be of independent interest.
arXiv Detail & Related papers (2025-05-23T20:58:55Z) - Neural network learns low-dimensional polynomials with SGD near the information-theoretic limit [75.4661041626338]
We study the problem of gradient descent learning of a single-index target function $f_*(boldsymbolx) = textstylesigma_*left(langleboldsymbolx,boldsymbolthetarangleright)$<n>We prove that a two-layer neural network optimized by an SGD-based algorithm learns $f_*$ with a complexity that is not governed by information exponents.
arXiv Detail & Related papers (2024-06-03T17:56:58Z) - A Unified Framework for Uniform Signal Recovery in Nonlinear Generative
Compressed Sensing [68.80803866919123]
Under nonlinear measurements, most prior results are non-uniform, i.e., they hold with high probability for a fixed $mathbfx*$ rather than for all $mathbfx*$ simultaneously.
Our framework accommodates GCS with 1-bit/uniformly quantized observations and single index models as canonical examples.
We also develop a concentration inequality that produces tighter bounds for product processes whose index sets have low metric entropy.
arXiv Detail & Related papers (2023-09-25T17:54:19Z) - Detection of Dense Subhypergraphs by Low-Degree Polynomials [72.4451045270967]
Detection of a planted dense subgraph in a random graph is a fundamental statistical and computational problem.
We consider detecting the presence of a planted $Gr(ngamma, n-alpha)$ subhypergraph in a $Gr(n, n-beta) hypergraph.
Our results are already new in the graph case $r=2$, as we consider the subtle log-density regime where hardness based on average-case reductions is not known.
arXiv Detail & Related papers (2023-04-17T10:38:08Z) - Online Learning with Adversaries: A Differential-Inclusion Analysis [52.43460995467893]
We introduce an observation-matrix-based framework for fully asynchronous online Federated Learning with adversaries.
Our main result is that the proposed algorithm almost surely converges to the desired mean $mu.$
We derive this convergence using a novel differential-inclusion-based two-timescale analysis.
arXiv Detail & Related papers (2023-04-04T04:32:29Z) - Sparse Signal Detection in Heteroscedastic Gaussian Sequence Models:
Sharp Minimax Rates [1.0309387309011746]
We study the signal detection problem against sparse alternatives, for known sparsity $s$.
We find minimax upper and lower bounds over the minimax separation radius $epsilon*$ and prove that they are always matching.
Our results reveal new phase transitions regarding the behavior of $epsilon*$ with respect to the level of sparsity, to the $Lt$ metric, and to the heteroscedasticity profile of $Sigma$.
arXiv Detail & Related papers (2022-11-15T23:53:39Z) - Efficient Signed Graph Sampling via Balancing & Gershgorin Disc Perfect
Alignment [51.74913666829224]
We show that for datasets with strong inherent anti-correlations, a suitable graph contains both positive and negative edge weights.
We propose a linear-time signed graph sampling method centered on the concept of balanced signed graphs.
Experimental results show that our signed graph sampling method outperformed existing fast sampling schemes noticeably on various datasets.
arXiv Detail & Related papers (2022-08-18T09:19:01Z) - Approximate Function Evaluation via Multi-Armed Bandits [51.146684847667125]
We study the problem of estimating the value of a known smooth function $f$ at an unknown point $boldsymbolmu in mathbbRn$, where each component $mu_i$ can be sampled via a noisy oracle.
We design an instance-adaptive algorithm that learns to sample according to the importance of each coordinate, and with probability at least $1-delta$ returns an $epsilon$ accurate estimate of $f(boldsymbolmu)$.
arXiv Detail & Related papers (2022-03-18T18:50:52Z) - Random Graph Matching in Geometric Models: the Case of Complete Graphs [21.689343447798677]
This paper studies the problem of matching two complete graphs with edge weights correlated through latent geometries.
We derive an approximate maximum likelihood estimator, which provably achieves, with high probability, perfect recovery of $pi*$.
As a side discovery, we show that the celebrated spectral algorithm of [Ume88] emerges as a further approximation to the maximum likelihood in the geometric model.
arXiv Detail & Related papers (2022-02-22T04:14:45Z) - A sublinear query quantum algorithm for s-t minimum cut on dense simple
graphs [1.0435741631709405]
An $soperatorname-t$ minimum cut in a graph corresponds to a minimum weight subset of edges whose removal disconnects $s$ and $t$.
In this work we describe a quantum algorithm for the minimum $soperatorname-t$ cut problem on undirected graphs.
arXiv Detail & Related papers (2021-10-29T07:35:46Z) - Fast Graph Sampling for Short Video Summarization using Gershgorin Disc
Alignment [52.577757919003844]
We study the problem of efficiently summarizing a short video into several paragraphs, leveraging recent progress in fast graph sampling.
Experimental results show that our algorithm achieves comparable video summarization as state-of-the-art methods, at a substantially reduced complexity.
arXiv Detail & Related papers (2021-10-21T18:43:00Z) - Improved Reconstruction of Random Geometric Graphs [3.930410971186142]
We consider the classic model of random geometric graphs where $n$ points are scattered uniformly in a square of area $n$.
We use a hybrid of graph distances and short-range estimates based on the number of common neighbors to estimate Euclidean distances.
Our method estimates Euclidean distances using a hybrid of graph distances and short-range estimates based on the number of common neighbors.
arXiv Detail & Related papers (2021-07-29T20:37:28Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.