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We propose a general approach to handle data contaminations that might disrupt the performance of feature selection and estimation procedures for high-dimensional linear models. Specifically, we consider the co-occurrence of mean-shift and…

Methodology · Statistics 2021-06-23 Luca Insolia , Francesca Chiaromonte , Runze Li , Marco Riani

In this paper, we provide an explicit probability distribution for classification purposes. It is derived from the Bayesian nonparametric mixture of Dirichlet process model, but with suitable modifications which remove unsuitable aspects of…

Applications · Statistics 2009-05-05 Ruth Fuentes-Garcia , Ramses H Mena , Stephen G Walker

Outlier detection aims to identify unusual data instances that deviate from expected patterns. The outlier detection is particularly challenging when outliers are context dependent and when they are defined by unusual combinations of…

Artificial Intelligence · Computer Science 2015-05-18 Charmgil Hong , Milos Hauskrecht

Biclustering is a class of techniques that simultaneously clusters the rows and columns of a matrix to sort heterogeneous data into homogeneous blocks. Although many algorithms have been proposed to find biclusters, existing methods suffer…

Machine Learning · Statistics 2020-02-11 Michelle N. Ngo , Dustin S. Pluta , Alexander N. Ngo , Babak Shahbaba

Analyzing sequence data usually leads to the discovery of interesting patterns and then anomaly detection. In recent years, numerous frameworks and methods have been proposed to discover interesting patterns in sequence data as well as…

Databases · Computer Science 2021-12-01 Wensheng Gan , Lili Chen , Shicheng Wan , Jiahui Chen , Chien-Ming Chen

In the realm of unsupervised image outlier detection, assigning outlier scores holds greater significance than its subsequent task: thresholding for predicting labels. This is because determining the optimal threshold on non-separable…

Computer Vision and Pattern Recognition · Computer Science 2024-07-16 Zhonghang Liu , Panzhong Lu , Guoyang Xie , Zhichao Lu , Wen-Yan Lin

Out-of-distribution detection (OOD) deals with anomalous input to neural networks. In the past, specialized methods have been proposed to reject predictions on anomalous input. Similarly, it was shown that feature extraction models in…

Machine Learning · Computer Science 2022-01-25 Jan Diers , Christian Pigorsch

This paper presents a new model called infinite mixtures of multivariate Gaussian processes, which can be used to learn vector-valued functions and applied to multitask learning. As an extension of the single multivariate Gaussian process,…

Machine Learning · Computer Science 2013-07-29 Shiliang Sun

With the recently rapid development in deep learning, deep neural networks have been widely adopted in many real-life applications. However, deep neural networks are also known to have very little control over its uncertainty for unseen…

Machine Learning · Computer Science 2019-04-23 Wenhu Chen , Yilin Shen , Hongxia Jin , William Wang

Data-driven anomaly detection methods typically build a model for the normal behavior of the target system, and score each data instance with respect to this model. A threshold is invariably needed to identify data instances with high (or…

Machine Learning · Statistics 2019-10-09 Sreelekha Guggilam , S. M. Arshad Zaidi , Varun Chandola , Abani Patra

To improve the predictability of complex computational models in the experimentally-unknown domains, we propose a Bayesian statistical machine learning framework utilizing the Dirichlet distribution that combines results of several…

Methodology · Statistics 2023-11-06 Vojtech Kejzlar , Léo Neufcourt , Witold Nazarewicz

Probabilistic finite mixture models are widely used for unsupervised clustering. These models can often be improved by adapting them to the topology of the data. For instance, in order to classify spatially adjacent data points similarly,…

Computer Vision and Pattern Recognition · Computer Science 2022-02-09 Jonathan Vacher , Claire Launay , Ruben Coen-Cagli

We present a probabilistic model for unsupervised alignment of high-dimensional time-warped sequences based on the Dirichlet Process Mixture Model (DPMM). We follow the approach introduced in (Kazlauskaite, 2018) of simultaneously…

Machine Learning · Statistics 2018-11-28 Ieva Kazlauskaite , Ivan Ustyuzhaninov , Carl Henrik Ek , Neill D. F. Campbell

This paper proposes a novel fast online methodology for outlier detection called the exception maximization outlier detection method(EMODM), which employs probabilistic models and statistical algorithms to detect abnormal patterns from the…

Machine Learning · Statistics 2025-06-03 Zhikun Zhang , Yiting Duan , Xiangjun Wang , Mingyuan Zhang

Anomaly detection is a field of intense research. Identifying low probability events in data/images is a challenging problem given the high-dimensionality of the data, especially when no (or little) information about the anomaly is…

Machine Learning · Computer Science 2022-04-13 José A. Padrón-Hidalgo , Valero Laparra , Gustau Camps-Valls

Rare data in a large-scale database are called outliers that reveal significant information in the real world. The subspace-based outlier detection is regarded as a feasible approach in very high dimensional space. However, the outliers…

Artificial Intelligence · Computer Science 2014-05-06 Zhana Bao

It is important to detect anomalous inputs when deploying machine learning systems. The use of larger and more complex inputs in deep learning magnifies the difficulty of distinguishing between anomalous and in-distribution examples. At the…

Machine Learning · Computer Science 2019-01-30 Dan Hendrycks , Mantas Mazeika , Thomas Dietterich

Deep networks often make confident, yet, incorrect, predictions when tested with outlier data that is far removed from their training distributions. Likelihoods computed by deep generative models (DGMs) are a candidate metric for outlier…

Machine Learning · Computer Science 2022-07-20 Kushal Chauhan , Barath Mohan U , Pradeep Shenoy , Manish Gupta , Devarajan Sridharan

Bayesian models that mix multiple Dirichlet prior parameters, called Multi-Dirichlet priors (MD) in this paper, are gaining popularity. Inferring mixing weights and parameters of mixed prior distributions seems tricky, as sums over…

Machine Learning · Statistics 2017-08-18 Christoph Carl Kling

We consider the problem of clustering grouped data with possibly non-exchangeable groups whose dependencies can be characterized by a known directed acyclic graph. To allow the sharing of clusters among the non-exchangeable groups, we…