Zhiheng Lyu


2024

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VideoScore: Building Automatic Metrics to Simulate Fine-grained Human Feedback for Video Generation
Xuan He | Dongfu Jiang | Ge Zhang | Max Ku | Achint Soni | Sherman Siu | Haonan Chen | Abhranil Chandra | Ziyan Jiang | Aaran Arulraj | Kai Wang | Quy Duc Do | Yuansheng Ni | Bohan Lyu | Yaswanth Narsupalli | Rongqi Fan | Zhiheng Lyu | Bill Yuchen Lin | Wenhu Chen
Proceedings of the 2024 Conference on Empirical Methods in Natural Language Processing

The recent years have witnessed great advances in video generation. However, the development of automatic video metrics is lagging significantly behind. None of the existing metric is able to provide reliable scores over generated videos. The main barrier is the lack of large-scale human-annotated dataset. In this paper, we release VideoFeedback, the first large-scale dataset containing human-provided multi-aspect score over 37.6K synthesized videos from 11 existing video generative models. We train VideoScore (initialized from Mantis)based on VideoFeedback to enable automatic video quality assessment. Experiments show that the Spearman’s correlation betweenVideoScore and humans can reach 77.1 on VideoFeedback-test, beating the prior best metrics by about 50 points. Further result onother held-out EvalCrafter, GenAI-Bench, and VBench show that VideoScore has consistently much higher correlation with humanjudges than other metrics. Due to these results, we believe VideoScore can serve as a great proxy for human raters to (1) rate different video models to track progress (2) simulate fine-grained human feedback in Reinforcement Learning with Human Feedback (RLHF) to improve current video generation models.

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Do LLMs Think Fast and Slow? A Causal Study on Sentiment Analysis
Zhiheng Lyu | Zhijing Jin | Fernando Gonzalez Adauto | Rada Mihalcea | Bernhard Schölkopf | Mrinmaya Sachan
Findings of the Association for Computational Linguistics: EMNLP 2024

Sentiment analysis (SA) aims to identify the sentiment expressed in a piece of text, often in the form of a review. Assuming a review and the sentiment associated with it, in this paper we formulate SA as a combination of two tasks: (1) a causal discovery task that distinguishes whether a review “primes” the sentiment (Causal Hypothesis C1), or the sentiment “primes” the review (Causal Hypothesis C2); and (2) the traditional prediction task to model the sentiment using the review as input. Using the peak-end rule in psychology, we classify a sample as C1 if its overall sentiment score approximates an average of all the sentence-level sentiments in the review, and as C2 if the overall sentiment score approximates an average of the peak and end sentiments. For the prediction task, we use the discovered causal mechanisms behind the samples to improve the performance of LLMs by proposing causal prompts that give the models an inductive bias of the underlying causal graph, leading to substantial improvements by up to 32.13 F1 points on zero-shot five-class SA.

2022

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Logical Fallacy Detection
Zhijing Jin | Abhinav Lalwani | Tejas Vaidhya | Xiaoyu Shen | Yiwen Ding | Zhiheng Lyu | Mrinmaya Sachan | Rada Mihalcea | Bernhard Schoelkopf
Findings of the Association for Computational Linguistics: EMNLP 2022

Reasoning is central to human intelligence. However, fallacious arguments are common, and some exacerbate problems such as spreading misinformation about climate change. In this paper, we propose the task of logical fallacy detection, and provide a new dataset (Logic) of logical fallacies generally found in text, together with an additional challenge set for detecting logical fallacies in climate change claims (LogicClimate). Detecting logical fallacies is a hard problem as the model must understand the underlying logical structure of the argument. We find that existing pretrained large language models perform poorly on this task. In contrast, we show that a simple structure-aware classifier outperforms the best language model by 5.46% F1 scores on Logic and 4.51% on LogicClimate. We encourage future work to explore this task since (a) it can serve as a new reasoning challenge for language models, and (b) it can have potential applications in tackling the spread of misinformation. Our dataset and code are available at https://github.com/causalNLP/logical-fallacy