Saved in:
Bibliographic Details
Main Authors: Lei, Yuan-Zheng, Gong, Yaobang, Yang, Xianfeng Terry
Format: Preprint
Published: 2024
Subjects:
Online Access:https://arxiv.org/abs/2404.09318
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866909399261380608
author Lei, Yuan-Zheng
Gong, Yaobang
Yang, Xianfeng Terry
author_facet Lei, Yuan-Zheng
Gong, Yaobang
Yang, Xianfeng Terry
contents Traffic flow modeling relies heavily on fundamental diagrams. However, deterministic fundamental diagrams, such as single or multi-regime models, cannot capture the uncertainty pattern that underlies traffic flow. To address this limitation, a sparse non-parametric regression model is proposed in this paper to formulate the stochastic fundamental diagram. Unlike parametric stochastic fundamental diagram models, a non-parametric model is insensitive to parameters, flexible, and applicable. The computation complexity and the huge memory required for training in the Gaussian process regression have been reduced by introducing the sparse Gaussian process regression. The paper also discusses how empirical knowledge influences the modeling process. The paper analyzes the influence of modeling empirical knowledge in the prior of the stochastic fundamental diagram model and whether empirical knowledge can improve the robustness and accuracy of the proposed model. By introducing several well-known single-regime fundamental diagram models as the prior and testing the model's robustness and accuracy with different sampling methods given real-world data, the authors find that empirical knowledge can only benefit the model under small inducing samples given a relatively clean and large dataset. A pure data-driven approach is sufficient to estimate and describe the pattern of the density-speed relationship.
format Preprint
id arxiv_https___arxiv_org_abs_2404_09318
institution arXiv
publishDate 2024
record_format arxiv
spellingShingle Unraveling stochastic fundamental diagrams considering empirical knowledge: modeling, limitation and further discussion
Lei, Yuan-Zheng
Gong, Yaobang
Yang, Xianfeng Terry
Applications
Traffic flow modeling relies heavily on fundamental diagrams. However, deterministic fundamental diagrams, such as single or multi-regime models, cannot capture the uncertainty pattern that underlies traffic flow. To address this limitation, a sparse non-parametric regression model is proposed in this paper to formulate the stochastic fundamental diagram. Unlike parametric stochastic fundamental diagram models, a non-parametric model is insensitive to parameters, flexible, and applicable. The computation complexity and the huge memory required for training in the Gaussian process regression have been reduced by introducing the sparse Gaussian process regression. The paper also discusses how empirical knowledge influences the modeling process. The paper analyzes the influence of modeling empirical knowledge in the prior of the stochastic fundamental diagram model and whether empirical knowledge can improve the robustness and accuracy of the proposed model. By introducing several well-known single-regime fundamental diagram models as the prior and testing the model's robustness and accuracy with different sampling methods given real-world data, the authors find that empirical knowledge can only benefit the model under small inducing samples given a relatively clean and large dataset. A pure data-driven approach is sufficient to estimate and describe the pattern of the density-speed relationship.
title Unraveling stochastic fundamental diagrams considering empirical knowledge: modeling, limitation and further discussion
topic Applications
url https://arxiv.org/abs/2404.09318