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Related papers: Time-causal and time-recursive wavelets

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We develop a timescale synthesis-based probabilistic approach for the modeling of locally stationary signals. Inspired by our previous work, the model involves zero-mean, complex Gaussian wavelet coefficients, whose distribution varies as a…

Statistics Theory · Mathematics 2020-02-10 Adrien Meynard , Bruno Torrésani

We present an improved model and theory for time-causal and time-recursive spatio-temporal receptive fields, obtained by a combination of Gaussian receptive fields over the spatial domain and first-order integrators or equivalently…

Computer Vision and Pattern Recognition · Computer Science 2021-01-25 Tony Lindeberg

In kernel methods, temporal information on the data is commonly included by using time-delayed embeddings as inputs. Recently, an alternative formulation was proposed by defining a gamma-filter explicitly in a reproducing kernel Hilbert…

Machine Learning · Statistics 2017-06-13 Steven Van Vaerenbergh , Simone Scardapane , Ignacio Santamaria

Mobile communication channels are often modeled as linear time-varying filters or, equivalently, as time-frequency integral operators with finite support in time and frequency. Such a characterization inherently assumes the signals are…

Information Theory · Computer Science 2007-07-16 Scott T. Rickard , Radu V. Balan , H. Vincent Poor , Sergio Verdu

Causal modelling is a tool for generating causal explanations of observed correlations and has led to a deeper understanding of correlations in quantum networks. Existing frameworks for quantum causality tend to focus on acyclic causal…

Quantum Physics · Physics 2024-03-14 V. Vilasini , Roger Colbeck

Leveraging the symmetries inherent to specific data domains for the construction of equivariant neural networks has lead to remarkable improvements in terms of data efficiency and generalization. However, most existing research focuses on…

Machine Learning · Computer Science 2024-01-23 David W. Romero , Erik J. Bekkers , Jakub M. Tomczak , Mark Hoogendoorn

Temporal causal discovery is a crucial task aimed at uncovering the causal relations within time series data. The latest temporal causal discovery methods usually train deep learning models on prediction tasks to uncover the causality…

Machine Learning · Computer Science 2024-06-25 Lingbai Kong , Wengen Li , Hanchen Yang , Yichao Zhang , Jihong Guan , Shuigeng Zhou

Time-series classification is essential across diverse domains, including medical diagnosis, industrial monitoring, financial forecasting, and human activity recognition. The Rocket algorithm has emerged as a simple yet powerful method,…

Machine Learning · Statistics 2025-02-25 Jorge Marco-Blanco , Rubén Cuevas

Time-reversal symmetry is a prevalent feature of microscopic physics, including operational quantum theory and classical general relativity. Previous works have studied indefinite causal structure using the language of operational quantum…

Quantum Physics · Physics 2024-06-27 Luke Mrini , Lucien Hardy

We merge computational mechanics' definition of causal states (predictively-equivalent histories) with reproducing-kernel Hilbert space (RKHS) representation inference. The result is a widely-applicable method that infers causal structure…

Machine Learning · Computer Science 2024-06-19 Nicolas Brodu , James P. Crutchfield

We propose a nonparametric bivariate time-varying coefficient model for longitudinal measurements with the occurrence of a terminal event that is subject to right censoring. The time-varying coefficients capture the longitudinal…

Methodology · Statistics 2021-11-10 Yue Wang , Bin Nan , Jack D. Kalbfleisch

Characteristic scale is a notion that pervades the geophysical sciences, but it has no widely accepted precise definition. The wavelet transform decomposes a time series into coefficients that are associated with different scales. The…

Methodology · Statistics 2010-07-26 Michael J. Keim , Donald B. Percival

Many natural and engineered time series -- equity returns, climate anomalies, turbulent velocities, neural recordings, packet-level network traffic -- are approximately self-similar: their horizon-$T$ distribution is tied to the horizon-$1$…

Machine Learning · Computer Science 2026-05-19 Andrea Morandi

This paper develops a novel statistical approach to characterize temporally localised cross-oscillatory interactions between channels in a functional brain network. Brain signals are generally nonstationary and the proposed framework uses…

Methodology · Statistics 2026-02-10 Haibo Wu , Marina I. Knight , Hernando Ombao

Causal discovery from observational data is an important tool in many branches of science. Under certain assumptions it allows scientists to explain phenomena, predict, and make decisions. In the large sample limit, sound and complete…

Machine Learning · Statistics 2021-07-13 Shami Nisimov , Yaniv Gurwicz , Raanan Y. Rohekar , Gal Novik

We provide a unified operational framework for the study of causality, non-locality and contextuality, in a fully device-independent and theory-independent setting. We define causaltopes, our chosen portmanteau of "causal polytopes", for…

Quantum Physics · Physics 2023-07-31 Stefano Gogioso , Nicola Pinzani

Time-series causal discovery (TSCD) is a fundamental problem of machine learning. However, existing synthetic datasets cannot properly evaluate or predict the algorithms' performance on real data. This study introduces the CausalTime…

Machine Learning · Computer Science 2023-10-04 Yuxiao Cheng , Ziqian Wang , Tingxiong Xiao , Qin Zhong , Jinli Suo , Kunlun He

A kernel-based framework for spatio-temporal data analysis is introduced that applies in situations when the underlying system dynamics are governed by a dynamic equation. The key ingredient is a representer theorem that involves…

Statistics Theory · Mathematics 2020-11-16 Oleg Szehr , Dario Azzimonti , Laura Azzimonti

Temporal networks representing a stream of timestamped edges are seemingly ubiquitous in the real-world. However, the massive size and continuous nature of these networks make them fundamentally challenging to analyze and leverage for…

Data Structures and Algorithms · Computer Science 2021-01-08 Nesreen K. Ahmed , Nick Duffield , Ryan A. Rossi

Many real-world graphs or networks are temporal, e.g., in a social network persons only interact at specific points in time. This information directs dissemination processes on the network, such as the spread of rumors, fake news, or…

Social and Information Networks · Computer Science 2021-08-23 Lutz Oettershagen , Nils M. Kriege , Christopher Morris , Petra Mutzel