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Xiaoqian Liu

14 accepted papers

2026

Agentic Reinforcement Learning with Implicit Step Rewards

ICLR 2026poster

Large language models (LLMs) are increasingly developed as autonomous agents using reinforcement learning (agentic RL) that reason and act in interactive environments. However, sparse and sometimes unverifiable rewards make it extremely challenging to assign credit when training LLM agents that serv…

Cited by 0SourceScholar
2026

SageLM: A Multi-aspect and Explainable Large Language Model for Speech Judgement

AAAI 2026technical

Speech-to-Speech (S2S) Large Language Models (LLMs) are foundational to natural human-computer interaction, enabling end-to-end spoken dialogue systems. However, evaluating these models remains a fundamental challenge. We propose SageLM, an end-to-end, multi-aspect, and explainable speech LLM for co

Cited by 0SourcePDFScholar
2026

WaveEx: Accelerating Flow Matching-based Speech Generation via Wavelet-guided Extrapolation

AAAI 2026technical

Flow matching-based generative models offer a principled approach to modeling continuous-time dynamics in speech generation. However, inference is often computationally expensive due to repeated neural network evaluations required by ODE solvers. We propose WaveEx, a training-free and plug-in accele

Cited by 0SourcePDFScholar
2025

A Modular-based Strategy for Mitigating Gradient Conflicts in Simultaneous Speech Translation

ICASSP 2025accepted

Simultaneous Speech Translation (SimulST) involves generating target language text while continuously processing streaming speech input, presenting significant real-time challenges. Multi-task learning is often employed to enhance SimulST performance but introduces optimization conflicts between pri…

Cited by 0SourceScholar
2025

Beyond Decoder-only: Large Language Models Can be Good Encoders for Machine Translation

ACL 2025finding

The field of neural machine translation (NMT) has changed with the advent of large language models (LLMs). Much of the recent emphasis in natural language processing (NLP) has been on modeling machine translation and many other problems using a single pre-trained Transformer decoder, while encoder-d…

2025

EPO: Explicit Policy Optimization for Strategic Reasoning in LLMs via Reinforcement Learning

ACL 2025long

Large Language Models (LLMs) have shown impressive reasoning capabilities in well-defined problems with clear solutions, such as mathematics and coding. However, they still struggle with complex real-world scenarios like business negotiations, which require strategic reasoning—an ability to navigate…

2025

SDPO: Segment-Level Direct Preference Optimization for Social Agents

ACL 2025long

Social agents powered by large language models (LLMs) can simulate human social behaviors but fall short in handling complex social dialogues. Direct Preference Optimization (DPO) has proven effective in aligning LLM behavior with human preferences across various agent tasks. However, standard DPO f…

2025

Step-level Verifier-guided Hybrid Test-Time Scaling for Large Language Models

EMNLP 2025

Test-Time Scaling (TTS) is a promising approach to progressively elicit the model’s intelligence during inference. Recently, training-based TTS methods, such as continued reinforcement learning (RL), have further surged in popularity, while training-free TTS methods are gradually fading from promine

2024

Bridging the Gaps of Both Modality and Language: Synchronous Bilingual CTC for Speech Translation and Speech Recognition

ICASSP 2024accepted

In this study, we present synchronous bilingual Connectionist Temporal Classification (CTC), an innovative framework that leverages dual CTC to bridge the gaps of both modality and language in the speech translation (ST) task. Utilizing transcript and translation as concurrent objectives for CTC, ou…

Cited by 0SourceScholar
2024

Position: Foundation Agents as the Paradigm Shift for Decision Making

ICML 2024poster

Decision making demands intricate interplay between perception, memory, and reasoning to discern optimal policies. Conventional approaches to decision making face challenges related to low sample efficiency and poor generalization. In contrast, foundation models in language and vision have showcased…

2024

Recent Advances in End-to-End Simultaneous Speech Translation

IJCAI 2024poster

Simultaneous speech translation (SimulST) is a demanding task that involves generating translations in real-time while continuously processing speech input. This paper offers a comprehensive overview of the recent developments in SimulST research, focusing on four major challenges. Firstly, the comp…

Cited by 2SourcePDFScholar
2024

Revisiting Interpolation Augmentation for Speech-to-Text Generation

ACL 2024findings

Speech-to-text (S2T) generation systems frequently face challenges in low-resource scenarios, primarily due to the lack of extensive labeled datasets. One emerging solution is constructing virtual training samples by interpolating inputs and labels, which has notably enhanced system generalization i…

2023

Bridging the Granularity Gap for Acoustic Modeling

ACL 2023findings

While Transformer has become the de-facto standard for speech, modeling upon the fine-grained frame-level features remains an open challenge of capturing long-distance dependencies and distributing the attention weights. We propose Progressive Down-Sampling (PDS) which gradually compresses the acous…

2023

CTC-based Non-autoregressive Speech Translation

ACL 2023long

Combining end-to-end speech translation (ST) and non-autoregressive (NAR) generation is promising in language and speech processing for their advantages of less error propagation and low latency. In this paper, we investigate the potential of connectionist temporal classification (CTC) for non-autor…