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The problem of pre-training data detection for large language models (LLMs) has received growing attention due to its implications in critical issues like copyright violation and test data contamination. Despite improved performance,…

Computation and Language · Computer Science 2025-02-13 Jingyang Zhang , Jingwei Sun , Eric Yeats , Yang Ouyang , Martin Kuo , Jianyi Zhang , Hao Frank Yang , Hai Li

Recovering a low-complexity signal from its noisy observations by regularization methods is a cornerstone of inverse problems and compressed sensing. Stable recovery ensures that the original signal can be approximated linearly by optimal…

Optimization and Control · Mathematics 2025-05-30 Tran T. A. Nghia , Huy N. Pham , Nghia V. Vo

We consider the Euclidean $k$-means clustering problem in a dynamic setting, where we have to explicitly maintain a solution (a set of $k$ centers) $S \subseteq \mathbb{R}^d$ subject to point insertions/deletions in $\mathbb{R}^d$. We…

Data Structures and Algorithms · Computer Science 2026-04-03 Sayan Bhattacharya , Martín Costa , Ermiya Farokhnejad , Shaofeng H. -C. Jiang , Yaonan Jin , Jianing Lou

We revisit classic string problems considered in the area of parameterized complexity, and study them through the lens of dynamic data structures. That is, instead of asking for a static algorithm that solves the given instance efficiently,…

Data Structures and Algorithms · Computer Science 2022-05-03 Jędrzej Olkowski , Michał Pilipczuk , Mateusz Rychlicki , Karol Węgrzycki , Anna Zych-Pawlewicz

We give some new results on sparse signal recovery in the presence of noise, for weighted spaces. Traditionally, were used dictionaries that have the norm equal to 1, but, for random dictionaries this condition is rarely satisfied.…

Functional Analysis · Mathematics 2016-01-27 L. Gavruta , G. Zamani Eskandani , P. Gavruta

Compressed Sensing decoding algorithms can efficiently recover an N dimensional real-valued vector x to within a factor of its best k-term approximation by taking m = 2klog(N/k) measurements y = Phi x. If the sparsity or approximate…

Numerical Analysis · Mathematics 2008-12-09 Rachel Ward

Conventional sparse phase retrieval schemes can recover sparse signals from the magnitude of linear measurements only up to a global phase ambiguity. This work proposes a novel approach that instead utilizes the magnitude of affine…

Information Theory · Computer Science 2021-05-25 Ming-Hsun Yang , Y. -W. Peter Hong , Jwo-Yuh Wu

We present two deterministic dynamic algorithms for the maximum matching problem. (1) An algorithm that maintains a $(2+\epsilon)$-approximate maximum matching in general graphs with $O(\text{poly}(\log n, 1/\epsilon))$ update time. (2) An…

Data Structures and Algorithms · Computer Science 2016-04-21 Sayan Bhattacharya , Monika Henzinger , Danupon Nanongkai

We provide simple and fast polynomial time approximation schemes (PTASs) for several variants of the max-sum diversification problem which, in its most basic form, is as follows: Given n points p_1,...,p_n in R^d and an integer k, select k…

Data Structures and Algorithms · Computer Science 2016-07-18 Alfonso Cevallos , Friedrich Eisenbrand , Rico Zenklusen

Consider the compressed sensing setup where the support $s^*$ of an $m$-sparse $d$-dimensional signal $x$ is to be recovered from $n$ linear measurements with a given algorithm. Suppose that the measurements are such that the algorithm does…

Information Theory · Computer Science 2021-03-10 Mohammad Mehrabi , Aslan Tchamkerten

We consider the recovery of sparse signals subject to sparse interference, as introduced in Studer et al., IEEE Trans. IT, 2012. We present novel probabilistic recovery guarantees for this framework, covering varying degrees of knowledge of…

Information Theory · Computer Science 2012-09-27 Graeme Pope , Annina Bracher , Christoph Studer

We present a theoretical and empirical analysis of the SyncRank algorithm for recovering a global ranking from noisy pairwise comparisons. By adopting a complex-valued data model where the true ranking is encoded in the phases of a…

Machine Learning · Statistics 2025-09-30 Yang Rao

Many applications concern sparse signals, for example, detecting anomalies from the differences between consecutive images taken by surveillance cameras. This paper focuses on the problem of recovering a K-sparse signal x in N dimensions.…

Machine Learning · Statistics 2013-02-06 Ping Li , Cun-Hui Zhang

Over the past years, there are increasing interests in recovering the signals from undersampling data where such signals are sparse under some orthogonal dictionary or tight framework, which is referred to be sparse synthetic model. More…

Information Theory · Computer Science 2012-02-10 Lianlin Li

Optimizing neural networks with noisy labels is a challenging task, especially if the label set contains real-world noise. Networks tend to generalize to reasonable patterns in the early training stages and overfit to specific details of…

Computer Vision and Pattern Recognition · Computer Science 2023-04-27 Timo Kaiser , Lukas Ehmann , Christoph Reinders , Bodo Rosenhahn

We propose extended coherence-based conditions for exact sparse support recovery using orthogonal matching pursuit (OMP) and orthogonal least squares (OLS). Unlike standard uniform guarantees, we embed some information about the decay of…

Information Theory · Computer Science 2015-10-09 Cédric Herzet , Angélique Drémeau , Charles Soussen

The impact of measurement imperfections on quantum metrology protocols has not been approached in a systematic manner so far. In this work, we tackle this issue by generalising firstly the notion of quantum Fisher information to account for…

Quantum Physics · Physics 2022-11-21 Yink Loong Len , Tuvia Gefen , Alex Retzker , Jan Kołodyński

In this paper, we consider the sparse phase retrieval problem, recovering an $s$-sparse signal $\bm{x}^{\natural}\in\mathbb{R}^n$ from $m$ phaseless samples $y_i=|\langle\bm{x}^{\natural},\bm{a}_i\rangle|$ for $i=1,\ldots,m$. Existing…

Numerical Analysis · Mathematics 2021-10-15 Jian-Feng Cai , Jingzhi Li , Xiliang Lu , Juntao You

The idea of compressed sensing is to exploit representations in suitable (overcomplete) dictionaries that allow to recover signals far beyond the Nyquist rate provided that they admit a sparse representation in the respective dictionary.…

Computer Vision and Pattern Recognition · Computer Science 2018-06-22 Michael Moeller , Otmar Loffeld , Juergen Gall , Felix Krahmer

The text-to-pattern Hamming distances problem asks to compute the Hamming distances between a given pattern of length $m$ and all length-$m$ substrings of a given text of length $n\ge m$. We focus on the $k$-mismatch version of the problem,…

Data Structures and Algorithms · Computer Science 2022-03-30 Raphaël Clifford , Paweł Gawrychowski , Tomasz Kociumaka , Daniel P. Martin , Przemysław Uznański