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Related papers: Wavelet Based Time Series Models with Time-Varying…

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In this paper, we write the time-varying parameter (TVP) regression model involving K explanatory variables and T observations as a constant coefficient regression model with KT explanatory variables. In contrast with much of the existing…

Econometrics · Economics 2021-10-01 Niko Hauzenberger , Florian Huber , Gary Koop , Luca Onorante

We present a method that models the evolution of an unbounded number of time series clusters by switching among an unknown number of regimes with linear dynamics. We develop a Bayesian non-parametric approach using a hierarchical Dirichlet…

Machine Learning · Statistics 2025-10-09 Adrián Pérez-Herrero , Paulo Félix , Jesús Presedo , Carl Henrik Ek

With the advent of new fabrication technologies, time-varying metasurfaces have emerged as novel platforms for exotic waveform shaping in microwaves and optics, providing an additional degree of freedom to design dynamically controllable…

Optics · Physics 2025-03-18 Suat Barış İplikçioğlu , M. I. Aksun

Recently, evolving networks are becoming a suitable form to model many real-world complex systems, due to their peculiarities to represent the systems and their constituting entities, the interactions between the entities and the…

Artificial Intelligence · Computer Science 2017-09-21 Angelo Impedovo , Corrado Loglisci , Michelangelo Ceci

Many time series exhibit changes both in level and in variability. Generally, it is more important to detect a change in the level, and changing or smoothly evolving variability can confound existing tests. This paper develops a framework…

Statistics Theory · Mathematics 2016-12-09 Tomasz Gorecki , Lajos Horvath , Piotr Kokoszka

Transient signals are often composed of a series of modes that have multivalued time-dependent instantaneous frequency (IF), which brings challenges to the development of signal processing technology. Fortunately, the group delay (GD) of…

Signal Processing · Electrical Eng. & Systems 2022-02-23 Haoran Dong , Gang Yu

Soft-thresholding is a sparse modeling method that is typically applied to wavelet denoising in statistical signal processing and analysis. It has a single parameter that controls a threshold level on wavelet coefficients and,…

Methodology · Statistics 2016-02-01 Katsuyuki Hagiwara

Forecasting the number of trips in bike-sharing systems and its volatility over time is crucial for planning and optimizing such systems. This paper develops timeseries models to forecast hourly count timeseries data, and estimate its…

Methodology · Statistics 2020-11-18 Alireza Hosseini , Reza Hosseini

Assume that $(X_t)_{t\in\Z}$ is a real valued time series admitting a common marginal density $f$ with respect to Lebesgue's measure. Donoho {\it et al.} (1996) propose a near-minimax method based on thresholding wavelets to estimate $f$ on…

Statistics Theory · Mathematics 2011-03-17 Irène Gannaz , Olivier Wintenberger

We consider parameter estimation, hypothesis testing and variable selection for partially time-varying coefficient models. Our asymptotic theory has the useful feature that it can allow dependent, nonstationary error and covariate…

Statistics Theory · Mathematics 2012-08-20 Ting Zhang , Wei Biao Wu

Time series forecasting has become an increasingly popular research area due to its critical applications in various real-world domains such as traffic management, weather prediction, and financial analysis. Despite significant…

Machine Learning · Computer Science 2024-08-22 Ninghui Feng , Songning Lai , Jiayu Yang , Fobao Zhou , Zhenxiao Yin , Hang Zhao

Transformers have achieved superior performances in many tasks in natural language processing and computer vision, which also triggered great interest in the time series community. Among multiple advantages of Transformers, the ability to…

Machine Learning · Computer Science 2023-05-15 Qingsong Wen , Tian Zhou , Chaoli Zhang , Weiqi Chen , Ziqing Ma , Junchi Yan , Liang Sun

This work presents a purely data-driven, wavelet-based framework for modal identification and reduced-order modeling of mechanical systems with assumed linear dynamics characterized by closely spaced modes with classical or non-classical…

Signal Processing · Electrical Eng. & Systems 2025-10-28 Anargyros Michaloliakos , Benjamin J. Chang , Lawrence A. Bergman , Alexander F. Vakakis

The linear and renormalized nonlinear analysis of the temporal evolution of drift-type modes in plasma flows with strong time-varying velocity shear is developed. Analysis is performed in the time domain without spectral decomposition in…

Plasma Physics · Physics 2009-07-31 V. S. Mikhailenko , V. V. Mikhailenko , K. N. Stepanov

In turbulent flows, energy production is associated with highly organized structures, known as coherent structures. Since these structures are three-dimensional, their detection remains challenging in the most common situation, when…

Fluid Dynamics · Physics 2023-09-12 Subharthi Chowdhuri , Tirtha Banerjee

Time series data is prevalent in a wide variety of real-world applications and it calls for trustworthy and explainable models for people to understand and fully trust decisions made by AI solutions. We consider the problem of building…

Machine Learning · Computer Science 2020-11-25 Tsung-Yu Hsieh , Suhang Wang , Yiwei Sun , Vasant Honavar

The shapelet transform is a form of feature extraction for time series, in which a time series is described by its similarity to each of a collection of `shapelets'. However it has previously suffered from a number of limitations, such as…

Machine Learning · Computer Science 2020-06-01 Patrick Kidger , James Morrill , Terry Lyons

Classification of time series signals has become an important construct and has many practical applications. With existing classifiers we may be able to accurately classify signals, however that accuracy may decline if using a reduced…

Machine Learning · Statistics 2021-09-22 Paul Grant , Md Zahidul Islam

We propose a new class of univariate nonstationary time series models, using the framework of modulated time series, which is appropriate for the analysis of rapidly-evolving time series as well as time series observations with missing…

The possibilities of the use of the coefficient of variation over a high threshold in tail modelling are discussed. The paper also considers multiple threshold tests for a generalized Pareto distribution, together with a threshold selection…

Statistics Theory · Mathematics 2015-10-02 J. Castillo , M. Padilla