English
Related papers

Related papers: On multifractals: a non-linear study of actigraphy…

200 papers

The characterization of heart dynamics with a view to distinguish abnormal from normal behavior is an interesting topic in clinical sciences. Here we present an analysis of the Electro-cardiogram (ECG) signals obtained under controlled…

Tissues and Organs · Quantitative Biology 2018-09-05 Snehal M. Shekatkar , Yamini Kotriwar , K. P. Harikrishnan , G. Ambika

Functional magnetic resonance imaging (fMRI) data provides information concerning activity in the brain and in particular the interactions between brain regions. Resting state fMRI data is widely used for inferring connectivities in the…

Applications · Statistics 2019-03-04 Christina Stoehr , John A D Aston , Claudia Kirch

Brain metabolism is controlled by complex regulation mechanisms. As part of their nature many complex systems show scaling behavior in their timeseries data. Corresponding scaling exponents can sometimes be used to characterize these…

Condensed Matter · Physics 2007-05-23 Stefan Thurner , Christian Windischberger , Ewald Moser , Markus Barth

We provide an alternative method for analysis of multifractal properties of time series. The new approach takes into account the behaviour of the whole multifractal profile of the generalized Hurst exponent $h(q)$ for all moment orders $q$,…

Statistical Finance · Quantitative Finance 2013-09-24 Dariusz Grech , Grzegorz Pamuła

Multiresolution Wavelet Transform and Detrended Fluctuation Analysis have been recently proven as excellent methods in the analysis of Heart Rate Variability, and in distinguishing between healthy subjects and patients with various…

We investigate if known extrinsic and intrinsic factors fully account for the complex features observed in recordings of human activity as measured from forearm motion in subjects undergoing their regular daily routine. We demonstrate that…

Biological Physics · Physics 2009-11-10 Kun Hu , Plamen Ch. Ivanov , Zhi Chen , Michael F. Hilton , H. Eugene Stanley , Steven A. Shea

Many physical and physiological signals exhibit complex scale-invariant features characterized by $1/f$ scaling and long-range power-law correlations, suggesting a possibly common control mechanism. Specifically, it has been suggested that…

Objective This study provides an objective measure based on actigraphy for Attention Deficit Hyperactivity Disorder (ADHD) diagnosis in children. We search for motor activity features that could allow further investigation into their…

Scaling temporal dynamics in functional MRI (fMRI) signals have been evidenced for a decade as intrinsic characteristics of ongoing brain activity (Zarahn et al., 1997). Recently, scaling properties were shown to fluctuate across brain…

Statistics Theory · Mathematics 2013-08-21 P. Ciuciu , G. Varoquaux , P. Abry , S. Sadaghiani , A. Kleinschmidt

Physical activity is crucial for human health. With the increasing availability of large-scale mobile health data, strong associations have been found between physical activity and various diseases. However, accurately capturing this…

Methodology · Statistics 2026-01-19 Xiaojing Sun , Bingxin Zhao , Fei Xue

This study investigates the sleep characteristics and brain activity of individuals in the gray zone of insomnia, a population that experiences sleep disturbances yet does not fully meet the clinical criteria for chronic insomnia. Thirteen…

Human-Computer Interaction · Computer Science 2024-11-18 Ha-Na Jo , Young-Seok Kweon , Seo-Hyun Lee

We investigate the clinical and prognostic significance of fractal dimension and detrended fluctuation analysis by comparing the group of patients with stable angina pectoris without previous myocardial infarction with the group of…

Medical Physics · Physics 2007-05-23 G. Krstacic , M. Martinis , E. Vargovic , A. Knezevic , A. Krstacic

Frailty and functional decline strongly influence treatment tolerance and outcomes in older patients with cancer, yet assessment is typically limited to infrequent clinic visits. We propose a multimodal wearable framework to estimate…

Background: Symptom rating scales in psychiatry are limited by reliance on self-report, and lack of predictive power. Actigraphy, a passive wearable-based method for measuring sleep and physical activity, offers objective, high-resolution…

Quantitative Methods · Quantitative Biology 2025-07-31 Dylan Hamitouche , Tihare Zamorano , Youcef Barkat , Deven Parekh , Lena Palaniyappan , David Benrimoh

Many models and real complex systems possess critical thresholds at which the systems shift from one sate to another. The discovery of the early warnings of the systems in the vicinity of critical point are of great importance to estimate…

Statistical Mechanics · Physics 2017-02-08 Longfeng Zhao , Wei Li , Chunbin Yang , Jihui Han , Zhu Su , Yijiang Zou , Xu Cai

Recently the statistical characterizations of financial markets based on physics concepts and methods attract considerable attentions. We used two possible procedures of analyzing multifractal properties of a time series. The first one uses…

Data Analysis, Statistics and Probability · Physics 2008-12-02 A. Ganchuk , V. Derbentsev , V. Soloviev

This work presents, the classification of user activities such as Rest, Walk and Run, on the basis of frequency component present in the acceleration data in a wireless sensor network environment. As the frequencies of the above mentioned…

Neural and Evolutionary Computing · Computer Science 2011-07-25 Annapurna Sharma , Amit Purwar , Young-Dong Lee Young-Sook Lee Wan-Young Chung

The accelerometer has become an almost ubiquitous device, providing enormous opportunities in healthcare monitoring beyond step counting or other average energy estimates in 15-60 second epochs. Objective: To develop an open data set with…

We study quantitatively the level of false multifractal signal one may encounter while analyzing multifractal phenomena in time series within multifractal detrended fluctuation analysis (MF-DFA). The investigated effect appears as a result…

Data Analysis, Statistics and Probability · Physics 2015-06-16 Dariusz Grech , Grzegorz Pamuła

Functional magnetic resonance imaging or functional MRI (fMRI) is a very popular tool used for differing brain regions by measuring brain activity. It is affected by physiological noise, such as head and brain movement in the scanner from…

Methodology · Statistics 2023-10-30 Fangyijie Wang , Michael Salter-Townshend