中文
相关论文

相关论文: Modelling an equivalent b-value in diffusion-weigh…

200 篇论文

Microscopic diffusion anisotropy ({\mu}A) has been recently gaining increasing attention for its ability to decouple the average compartment anisotropy from orientation dispersion. Advanced diffusion MRI sequences, such as double diffusion…

Feature selection is fundamental to robust data-centric AI, but most existing methods optimize predictive performance under a single data distribution. This often selects spurious features that fail under distribution shifts. Motivated by…

机器学习 · 计算机科学 2026-03-24 Arun Vignesh Malarkkan , Xinyuan Wang , Kunpeng Liu , Denghui Zhang , Yanjie Fu

Diffusion probabilistic models (DPMs) represent a class of powerful generative models. Despite their success, the inference of DPMs is expensive since it generally needs to iterate over thousands of timesteps. A key problem in the inference…

机器学习 · 计算机科学 2022-05-04 Fan Bao , Chongxuan Li , Jun Zhu , Bo Zhang

A new probabilistic post-processing method for wind vectors is presented in a distributional regression framework employing the bivariate Gaussian distribution. In contrast to previous studies all parameters of the distribution are…

应用统计 · 统计学 2019-07-26 Moritz N. Lang , Georg J. Mayr , Reto Stauffer , Achim Zeileis

A particle with internal unobserved states diffusing in a force field will generally display effective advection-diffusion. The drift velocity is proportional to the mobility averaged over the internal states, or effective mobility, while…

统计力学 · 物理学 2017-10-13 Erik Aurell , Stefano Bo

This invited feature article introduces and provides an extensive simulation study of a new Approximate Bayesian Computation (ABC) framework for estimating the posterior distribution and the maximum likelihood estimate (MLE) of the…

统计方法学 · 统计学 2024-09-12 George Karabatsos

Distance weighted discrimination (DWD) is a linear discrimination method that is particularly well-suited for classification tasks with high-dimensional data. The DWD coefficients minimize an intuitive objective function, which can solved…

统计方法学 · 统计学 2020-10-08 Eric F. Lock

Ab initio modeling of dynamic structure factors (DSF) and related density response properties in the warm dense matter (WDM) regime is a challenging computational task. The DSF, convolved with a probing X-ray beam and instrument function,…

Background and Objective: This proof of concept study investigates mathematical modelling of blood flow and oxygen transport in cerebral microcirculation, focusing on understanding hemodynamic responses. By coupling oxygen transport models…

数值分析 · 数学 2024-11-19 Maryam Samavaki , Santtu Söderholm , Arash Zarrin Nia , Sampsa Pursiainen

A notable issue, the proper description of mass and charge distributions of fission fragments within nonadiabatic descriptions of fission dynamics, is investigated by performing double particle number projection on the outcomes of…

核理论 · 物理学 2024-10-15 Yun Huang , Xiang-Xiang Sun , Lu Guo

Models of diffusion MRI within a voxel are useful for making inferences about the properties of the tissue and inferring fiber orientation distribution used by tractography algorithms. A useful model must fit the data accurately. However,…

Training-free diffusion guidance offers a flexible framework for leveraging off-the-shelf classifiers without additional training. Yet, current approaches hinge on posterior approximations via Tweedie's formula, which often yield unreliable…

机器学习 · 计算机科学 2026-05-19 Van Khoa Nguyen , Lionel Blondé , Alexandros Kalousis

We investigate diffusion models generating synthetic samples from the probability distribution represented by the Ground Truth (GT) samples. We focus on how GT sample information is encoded in the Score Function (SF), computed (not…

机器学习 · 计算机科学 2025-03-28 Hamidreza Behjoo , Michael Chertkov

The effects of a "diffusing diffusivity" (DD), a stochastically time-varying diffusion coefficient, are explored within the frameworks of three different forms of fractional Brownian motion (FBM): (i) the Langevin equation driven by…

统计力学 · 物理学 2025-04-29 Wei Wang , Aleksei V. Chechkin , Ralf Metzler

Data-dependent metrics are powerful tools for learning the underlying structure of high-dimensional data. This article develops and analyzes a data-dependent metric known as diffusion state distance (DSD), which compares points using a…

机器学习 · 统计学 2020-03-10 Lenore Cowen , Kapil Devkota , Xiaozhe Hu , James M. Murphy , Kaiyi Wu

In this paper, we derive closed-form exact expressions for the main statistics of the ratio of squared alpha-mu random variables, which are of interest in many scenarios for future wireless networks where generalized distributions are more…

We report on a general and automatic data-driven background distribution shape estimation method using neural autoregressive flows (NAF), which is one of the deep generative learning methods. Data-driven background estimation is…

高能物理 - 唯象学 · 物理学 2020-08-11 Suyong Choi , Jaehoon Lim , Hayoung Oh

Stochastic differential equations (SDEs) or diffusions are continuous-valued continuous-time stochastic processes widely used in the applied and mathematical sciences. Simulating paths from these processes is usually an intractable problem,…

统计计算 · 统计学 2020-05-27 Qi Wang , Vinayak Rao , Yee Whye Teh

Variable selection for high-dimensional, highly correlated data has long been a challenging problem, often yielding unstable and unreliable models. We propose a resample-aggregate framework that exploits diffusion models' ability to…

统计方法学 · 统计学 2025-08-20 Minjie Wang , Xiaotong Shen , Wei Pan

Diffusion is a fundamental physical phenomenon with critical applications in fields such as metallurgy, cell biology, and population dynamics. While standard diffusion is well-understood, anomalous diffusion often requires complex non-local…

统计力学 · 物理学 2026-01-16 Gabriel Barreiro , Vladimir Pérez-Veloz