arXiv Machine Learning

Understanding the Inner Workings of a State-Space Foundation Model for Limit Order Books

arXiv:2610. 28753v1 Announce Type: cross Abstract: Autoregressive foundation models offer state-of-the-art capabilities to simulate the market by generating the message flow of limit order books (LOBs).

arXiv Machine Learning
Oct 21

LOB-Impact Benchmark: Emergent Market Impact in Generative Limit Order Book Models

arXiv:2610.27100v1 Announce Type: cross Abstract: Realistic market impact is essential for generative limit order book (LOB) models to serve as world models for trading agents. If a simulator mispric...

By George Nigmatulin, Valentin Mohl, Sascha Frey, Kang Li, Aramis Marti-Shahandeh, Mihai Cucuringu, Anisoara Calinescu, Jakob Foerster, Stefan Zohren
arXiv AI
Sep 28

UQ-LOB: Uncertainty-Aware Limit Order Book Mid-Price Forecasting

UQ-LOB is a lightweight, encoder‑agnostic module that adds uncertainty quantification to any pretrained limit order book (LOB) encoder. It offers two variants: UQ‑regression, which outputs a calibrated Gaussian over future tick displacement, and UQ‑classification, which outputs a categorical distribution over down/up/stationary. On 5.2 billion LOB events across seven cryptocurrency assets, UQ‑regression achieves near‑nominal 68 % interval coverage, and selecting the top 10 % most confident predictions boosts directional macro F1 by 0.11–0.15 for regression and 0.05–0.11 for classification, reaching F1 scores of 0.88 (down) and 0.83 (up) at a 5‑second horizon.

By Derrick Gilchrist Edward Manoharan, Eljas Linna, Kestutis Baltakys, Hao Dong, Juho Kanniainen
arXiv AI
Aug 26

Do LLMs Understand Limit Order Book Dynamics?

A large language model trained on synthetic limit order book data can generate valid sequences of LOB events with near‑perfect accuracy, yet its internal world model does not capture the true state of the book. This shortfall results in biased estimates and misleading predictability when the model is used to forecast future LOB events. The study introduces new tests for an LLM’s world model, extending previous deterministic analyses to the stochastic dynamics inherent in limit order books.

By Junxiao Chen, Paul Glasserman
arXiv Machine Learning
Oct 12

Market Impact Estimation via Causal Foundation Models

The paper introduces a Causal Market Simulator using a continuous‑time causal prior‑data fitted network (PFN) to estimate market impact, addressing bias from informational flow that traditional models overlook. On a synthetic market prior with adjustable confounding, the PFN matches an unbiased oracle while a naive estimator overestimates by up to 68%. In zero‑shot tests on real limit‑order books and equity data, the model’s intervention responses align with ground‑truth scales and improve correlation with measured impact when a recurrent state‑space variant is used.

By Dennis Thumm, Ying Chen
arXiv Machine Learning
Sep 22

Robust Market Making with Hawkes Order Flow and Price Impact via Adversarial Reinforcement Learning

The paper proposes an adversarial reinforcement‑learning framework for market making that incorporates Hawkes‑process driven order arrivals and trade‑induced price impact, addressing limitations of prior Poisson‑based models. An LSTM module captures temporal dependencies in recent observations to handle increased non‑stationarity, and the authors analyze equilibrium properties and introduce a robustness evaluation protocol focused on the left tail of returns. Experiments across diverse market regimes demonstrate that the method improves left‑tail performance, especially under strong Hawkes excitation and moderate price impact, without relying on a terminal inventory bias.

By Hao Yang, Zhenguo Xu