Shubhankar Singh


2024

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Jigsaw Pieces of Meaning: Modeling Discourse Coherence with Informed Negative Sample Synthesis
Shubhankar Singh
Findings of the Association for Computational Linguistics: EACL 2024

Coherence in discourse is fundamental for comprehension and perception. Much research on coherence modeling has focused on better model architectures and training setups optimizing on the permuted document task, where random permutations of a coherent document are considered incoherent. However, there’s very limited work on creating “informed” synthetic incoherent samples that better represent or mimic incoherence. We source a diverse positive corpus for local coherence and propose six rule-based methods leveraging information from Constituency trees, Part-of-speech, semantic overlap and more, for “informed” negative sample synthesis for better representation of incoherence. We keep a straightforward training setup for local coherence modeling by fine-tuning popular transformer models, and aggregate local scores for global coherence. We evaluate on a battery of independent downstream tasks to assess the impact of improved negative sample quality. We assert that a step towards optimality for coherence modeling requires better negative sample synthesis in tandem with model improvements.

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FlowVQA: Mapping Multimodal Logic in Visual Question Answering with Flowcharts
Shubhankar Singh | Purvi Chaurasia | Yerram Varun | Pranshu Pandya | Vatsal Gupta | Vivek Gupta | Dan Roth
Findings of the Association for Computational Linguistics ACL 2024

Existing benchmarks for visual question answering lack in visual grounding and complexity, particularly in evaluating spatial reasoning skills. We introduce FlowVQA, a novel benchmark aimed at assessing the capabilities of visual question-answering multimodal language models in reasoning with flowcharts as visual contexts. FlowVQA comprises 2,272 carefully generated and human-verified flowchart images from three distinct content sources, along with 22,413 diverse question-answer pairs, to test a spectrum of reasoning tasks, including information localization, decision-making, and logical progression. We conduct a thorough baseline evaluation on a suite of both open-source and proprietary multimodal language models using various strategies, followed by an analysis of directional bias. The results underscore the benchmark’s potential as a vital tool for advancing the field of multimodal modeling, providing a focused and challenging environment for enhancing model performance in visual and logical reasoning tasks.