Efficient Generation of Hidden Outliers for Improved Outlier Detection
- URL: http://arxiv.org/abs/2402.03846v2
- Date: Mon, 26 Aug 2024 11:58:22 GMT
- Title: Efficient Generation of Hidden Outliers for Improved Outlier Detection
- Authors: Jose Cribeiro-Ramallo, Vadim Arzamasov, Klemens Böhm,
- Abstract summary: Outlier generation is a popular technique used for solving important outlier detection tasks.
Existing methods disregard the'multiple views' property of outliers in high-dimensional spaces.
We propose BISECT, a new outlier generation method that creates realistic outliers mimicking said property.
- Score: 4.103281325880475
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: Outlier generation is a popular technique used for solving important outlier detection tasks. Generating outliers with realistic behavior is challenging. Popular existing methods tend to disregard the 'multiple views' property of outliers in high-dimensional spaces. The only existing method accounting for this property falls short in efficiency and effectiveness. We propose BISECT, a new outlier generation method that creates realistic outliers mimicking said property. To do so, BISECT employs a novel proposition introduced in this article stating how to efficiently generate said realistic outliers. Our method has better guarantees and complexity than the current methodology for recreating 'multiple views'. We use the synthetic outliers generated by BISECT to effectively enhance outlier detection in diverse datasets, for multiple use cases. For instance, oversampling with BISECT reduced the error by up to 3 times when compared with the baselines.
Related papers
- ALTBI: Constructing Improved Outlier Detection Models via Optimization of Inlier-Memorization Effect [2.3961612657966946]
Outlier detection (OD) is the task of identifying unusual observations (or outliers) from a given or upcoming data.
Inlier-memorization (IM) effect suggests that generative models memorize inliers before outliers in early learning stages.
We propose a theoretically principled method to address UOD tasks by maximally utilizing the IM effect.
arXiv Detail & Related papers (2024-08-19T08:40:53Z) - Regularized Contrastive Partial Multi-view Outlier Detection [76.77036536484114]
We propose a novel method named Regularized Contrastive Partial Multi-view Outlier Detection (RCPMOD)
In this framework, we utilize contrastive learning to learn view-consistent information and distinguish outliers by the degree of consistency.
Experimental results on four benchmark datasets demonstrate that our proposed approach could outperform state-of-the-art competitors.
arXiv Detail & Related papers (2024-08-02T14:34:27Z) - Diversified Outlier Exposure for Out-of-Distribution Detection via
Informative Extrapolation [110.34982764201689]
Out-of-distribution (OOD) detection is important for deploying reliable machine learning models on real-world applications.
Recent advances in outlier exposure have shown promising results on OOD detection via fine-tuning model with informatively sampled auxiliary outliers.
We propose a novel framework, namely, Diversified Outlier Exposure (DivOE), for effective OOD detection via informative extrapolation based on the given auxiliary outliers.
arXiv Detail & Related papers (2023-10-21T07:16:09Z) - Are we really making much progress in unsupervised graph outlier
detection? Revisiting the problem with new insight and superior method [36.72922385614812]
UNOD focuses on detecting two kinds of typical outliers in graphs: the structural outlier and the contextual outlier.
We find that the most widely-used outlier injection approach has a serious data leakage issue.
We propose a new framework, Variance-based Graph Outlier Detection (VGOD), which combines our variance-based model and attribute reconstruction model to detect outliers in a balanced way.
arXiv Detail & Related papers (2022-10-24T04:09:35Z) - Canary in a Coalmine: Better Membership Inference with Ensembled
Adversarial Queries [53.222218035435006]
We use adversarial tools to optimize for queries that are discriminative and diverse.
Our improvements achieve significantly more accurate membership inference than existing methods.
arXiv Detail & Related papers (2022-10-19T17:46:50Z) - Unsupervised Outlier Detection using Memory and Contrastive Learning [53.77693158251706]
We think outlier detection can be done in the feature space by measuring the feature distance between outliers and inliers.
We propose a framework, MCOD, using a memory module and a contrastive learning module.
Our proposed MCOD achieves a considerable performance and outperforms nine state-of-the-art methods.
arXiv Detail & Related papers (2021-07-27T07:35:42Z) - DEALIO: Data-Efficient Adversarial Learning for Imitation from
Observation [57.358212277226315]
In imitation learning from observation IfO, a learning agent seeks to imitate a demonstrating agent using only observations of the demonstrated behavior without access to the control signals generated by the demonstrator.
Recent methods based on adversarial imitation learning have led to state-of-the-art performance on IfO problems, but they typically suffer from high sample complexity due to a reliance on data-inefficient, model-free reinforcement learning algorithms.
This issue makes them impractical to deploy in real-world settings, where gathering samples can incur high costs in terms of time, energy, and risk.
We propose a more data-efficient IfO algorithm
arXiv Detail & Related papers (2021-03-31T23:46:32Z) - Homophily Outlier Detection in Non-IID Categorical Data [43.51919113927003]
This work introduces a novel outlier detection framework and its two instances to identify outliers in categorical data.
It first defines and incorporates distribution-sensitive outlier factors and their interdependence into a value-value graph-based representation.
The learned value outlierness allows for either direct outlier detection or outlying feature selection.
arXiv Detail & Related papers (2021-03-21T23:29:33Z) - AdaLAM: Revisiting Handcrafted Outlier Detection [106.38441616109716]
Local feature matching is a critical component of many computer vision pipelines.
We propose a hierarchical pipeline for effective outlier detection as well as integrate novel ideas which in sum lead to AdaLAM.
AdaLAM is designed to effectively exploit modern parallel hardware, resulting in a very fast, yet very accurate, outlier filter.
arXiv Detail & Related papers (2020-06-07T20:16:36Z)
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.