English
Related papers

Related papers: A Fast Greedy Algorithm for Outlier Mining

200 papers

Categorization is one of the basic tasks in machine learning and data analysis. Building on formal concept analysis (FCA), the starting point of the present work is that different ways to categorize a given set of objects exist, which…

Artificial Intelligence · Computer Science 2023-12-21 Marcel Boersma , Krishna Manoorkar , Alessandra Palmigiano , Mattia Panettiere , Apostolos Tzimoulis , Nachoem Wijnberg

Weighted Outlier Detection is a method for identifying unusual or anomalous data points in a dataset, which can be caused by various factors like human error, fraud, or equipment malfunctions. Detecting outliers can reveal vital information…

Machine Learning · Computer Science 2023-06-13 Ravindrakumar Purohit , Jai Prakash Verma , Rachna Jain , Madhuri Bhavsar

In real world, our datasets often contain outliers. Moreover, the outliers can seriously affect the final machine learning result. Most existing algorithms for handling outliers take high time complexities (e.g. quadratic or cubic…

Computational Geometry · Computer Science 2020-02-28 Hu Ding , Zixiu Wang

This paper examines the problem of locating outlier columns in a large, otherwise low-rank, matrix. We propose a simple two-step adaptive sensing and inference approach and establish theoretical guarantees for its performance; our results…

Information Theory · Computer Science 2015-06-22 Xingguo Li , Jarvis Haupt

An outlier is an observation or a data point that is far from rest of the data points in a given dataset or we can be said that an outlier is away from the center of mass of observations. Presence of outliers can skew statistical measures…

Machine Learning · Computer Science 2021-06-17 Amulya Agarwal , Nitin Gupta

Outlier detection is critical in real applications to prevent financial fraud, defend network intrusions, or detecting imminent device failures. To reduce the human effort in evaluating outlier detection results and effectively turn the…

Machine Learning · Computer Science 2023-09-04 Yu Wang , Lei Cao , Yizhou Yan , Samuel Madden

Distance-based outlier detection is widely adopted in many fields, e.g., data mining and machine learning, because it is unsupervised, can be employed in a generic metric space, and does not have any assumptions of data distributions. Data…

Databases · Computer Science 2021-10-22 Daichi Amagata , Makoto Onizuka , Takahiro Hara

Outliers widely occur in big-data applications and may severely affect statistical estimation and inference. In this paper, a framework of outlier-resistant estimation is introduced to robustify an arbitrarily given loss function. It has a…

Methodology · Statistics 2023-04-20 Yiyuan She , Zhifeng Wang , Jiahui Shen

Observations in data which are significantly different from its neighbouring points but cannot be classified as noise are known as anomalies or outliers. These anomalies are a cause of concern and a timely warning about their presence could…

Applications · Statistics 2020-06-09 Krishnam Kapoor

This paper presents a batch-wise density-based clustering approach for local outlier detection in massive-scale datasets. Unlike the well-known traditional algorithms, which assume that all the data is memory-resident, our proposed method…

Machine Learning · Computer Science 2021-07-06 Sayyed Ahmad Naghavi Nozad , Maryam Amir Haeri , Gianluigi Folino

The task of outlier detection is to find small groups of data objects that are exceptional when compared with rest large amount of data. Detection of such outliers is important for many applications such as fraud detection and customer…

Databases · Computer Science 2007-05-23 Zengyou He , Xiaofei Xu , Shengchun Deng

Many machine learning classification systems lack competency awareness. Specifically, many systems lack the ability to identify when outliers (e.g., samples that are distinct from and not represented in the training data distribution) are…

Machine Learning · Computer Science 2020-07-03 Matthew Cook , Alina Zare , Paul Gader

We study greedy-type algorithms such that at a greedy step we pick several dictionary elements contrary to a single dictionary element in standard greedy-type algorithms. We call such greedy algorithms {\it super greedy algorithms}. The…

Numerical Analysis · Mathematics 2010-10-27 Entao Liu , Vladimir N. Temlyakov

Outlier detection in high-dimensional data is a challenging yet important task, as it has applications in, e.g., fraud detection and quality control. State-of-the-art density-based algorithms perform well because they 1) take the local…

Artificial Intelligence · Computer Science 2016-11-02 Bas van Stein , Matthijs van Leeuwen , Thomas Bäck

This paper considers $k$-means clustering in the presence of noise. It is known that $k$-means clustering is highly sensitive to noise, and thus noise should be removed to obtain a quality solution. A popular formulation of this problem is…

Data Structures and Algorithms · Computer Science 2020-04-14 Sungjin Im , Mahshid Montazer Qaem , Benjamin Moseley , Xiaorui Sun , Rudy Zhou

In this paper, we study the problem of {\em $k$-center clustering with outliers}. The problem has many important applications in real world, but the presence of outliers can significantly increase the computational complexity. Though a…

Machine Learning · Computer Science 2023-01-10 Hu Ding , Ruomin Huang , Kai Liu , Haikuo Yu , Zixiu Wang

This note investigates the problem of detecting outliers in longitudinal data. It compares well-known methods used in official statistics with proposals from the fields of data mining and machine learning that are based on the distance…

Methodology · Statistics 2025-07-30 Marcello D'Orazio

We derive a convex optimization problem for the task of segmenting sequential data, which explicitly treats presence of outliers. We describe two algorithms for solving this problem, one exact and one a top-down novel approach, and we…

Machine Learning · Computer Science 2014-11-19 Itamar Katz , Koby Crammer

Outlier detection has gained increasing interest in recent years, due to newly emerging technologies and the huge amount of high-dimensional data that are now available. Outlier detection can help practitioners to identify unwanted noise…

Statistics Theory · Mathematics 2021-05-20 Mads Lindskou , Torben Tvedebrink , Poul Svante Eriksen , Niels Morling

In dictionary selection, several atoms are selected from finite candidates that successfully approximate given data points in the sparse representation. We propose a novel efficient greedy algorithm for dictionary selection. Not only does…

Machine Learning · Computer Science 2018-09-10 Kaito Fujii , Tasuku Soma