Search Results for author: Song Wei

Found 13 papers, 2 papers with code

Scene-Driven Multimodal Knowledge Graph Construction for Embodied AI

no code implementations7 Nov 2023 Song Yaoxian, Sun Penglei, Liu Haoyu, Li Zhixu, Song Wei, Xiao Yanghua, Zhou Xiaofang

Currently, knowledge base for embodied tasks is missing and most existing work use general knowledge base or pre-trained models to enhance the intelligence of an agent.

General Knowledge graph construction

INTAGS: Interactive Agent-Guided Simulation

no code implementations4 Sep 2023 Song Wei, Andrea Coletta, Svitlana Vyetrenko, Tucker Balch

To adapt to any environment with interactive sequential decision making agents, INTAGS formulates the simulator as a stochastic policy in reinforcement learning.

Algorithmic Trading Causal Inference +3

Transfer Learning for Causal Effect Estimation

no code implementations16 May 2023 Song Wei, Hanyu Zhang, Ronald Moore, Rishikesan Kamaleswaran, Yao Xie

We present a Transfer Causal Learning (TCL) framework when target and source domains share the same covariate/feature spaces, aiming to improve causal effect estimation accuracy in limited data.

regression Transfer Learning

Causal Structural Learning from Time Series: A Convex Optimization Approach

no code implementations26 Jan 2023 Song Wei, Yao Xie

Structural learning, which aims to learn directed acyclic graphs (DAGs) from observational data, is foundational to causal reasoning and scientific discovery.

Time Series Time Series Analysis

Causal Graph Discovery from Self and Mutually Exciting Time Series

no code implementations26 Jan 2023 Song Wei, Yao Xie, Christopher S. Josef, Rishikesan Kamaleswaran

We present a generalized linear structural causal model, coupled with a novel data-adaptive linear regularization, to recover causal directed acyclic graphs (DAGs) from time series.

Causal Discovery Time Series +1

Online Kernel CUSUM for Change-Point Detection

1 code implementation28 Nov 2022 Song Wei, Yao Xie

We present a computationally efficient online kernel Cumulative Sum (CUSUM) method for change-point detection that utilizes the maximum over a set of kernel statistics to account for the unknown change-point location.

Change Point Detection

Optimal Sub-sampling to Boost Power of Kernel Sequential Change-point Detection

no code implementations26 Oct 2022 Song Wei, Chaofan Huang

We present a novel scheme to boost detection power for kernel maximum mean discrepancy based sequential change-point detection procedures.

Change Point Detection

Granger Causal Chain Discovery for Sepsis-Associated Derangements via Continuous-Time Hawkes Processes

1 code implementation9 Sep 2022 Song Wei, Yao Xie, Christopher S. Josef, Rishikesan Kamaleswaran

Modern health care systems are conducting continuous, automated surveillance of the electronic medical record (EMR) to identify adverse events with increasing frequency; however, many events such as sepsis do not have elucidated prodromes (i. e., event chains) that can be used to identify and intercept the adverse event early in its course.

Causal Graph Discovery from Self and Mutually Exciting Time Series

no code implementations4 Jun 2021 Song Wei, Yao Xie, Christopher S. Josef, Rishikesan Kamaleswaran

We present a generalized linear structural causal model, coupled with a novel data-adaptive linear regularization, to recover causal directed acyclic graphs (DAGs) from time series.

Causal Discovery feature selection +2

Noisy Gradient Descent Converges to Flat Minima for Nonconvex Matrix Factorization

no code implementations24 Feb 2021 Tianyi Liu, Yan Li, Song Wei, Enlu Zhou, Tuo Zhao

Numerous empirical evidences have corroborated the importance of noise in nonconvex optimization problems.

Inferring serial correlation with dynamic backgrounds

no code implementations26 Jan 2021 Song Wei, Yao Xie, Dobromir Rahnev

Sequential data with serial correlation and an unknown, unstructured, and dynamic background is ubiquitous in neuroscience, psychology, and econometrics.

Statistics Theory Methodology Statistics Theory

Goodness-of-Fit Test for Mismatched Self-Exciting Processes

no code implementations16 Jun 2020 Song Wei, Shixiang Zhu, Minghe Zhang, Yao Xie

Recently there have been many research efforts in developing generative models for self-exciting point processes, partly due to their broad applicability for real-world applications.

Point Processes

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