Maitrey Mehta


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A Universal Dependencies Treebank for Gujarati
Mayank Jobanputra | Maitrey Mehta | Çağrı Çöltekin
Proceedings of the Joint Workshop on Multiword Expressions and Universal Dependencies (MWE-UD) @ LREC-COLING 2024

The Universal Dependencies (UD) project has presented itself as a valuable platform to develop various resources for the languages of the world. We present and release a sample treebank for the Indo-Aryan language of Gujarati – a widely spoken language with little linguistic resources. This treebank is the first labeled dataset for dependency parsing in the language and the script (the Gujarati script). The treebank contains 187 part-of-speech and dependency annotated sentences from diverse genres. We discuss various idiosyncratic examples, annotation choices and present an elaborate corpus along with agreement statistics. We see this work as a valuable resource and a stepping stone for research in Gujarati Computational Linguistics.

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Promptly Predicting Structures: The Return of Inference
Maitrey Mehta | Valentina Pyatkin | Vivek Srikumar
Proceedings of the 2024 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies (Volume 1: Long Papers)

Prompt-based methods have been used extensively across NLP to build zero- and few-shot label predictors. Many NLP tasks are naturally structured: that is, their outputs consist of multiple labels which constrain each other. Annotating data for such tasks can be cumbersome. Can the promise of the prompt-based paradigm be extended to such structured outputs? In this paper, we present a framework for constructing zero- and few-shot linguistic structure predictors. Our key insight is that we can use structural constraints—and combinatorial inference derived from them—to filter out inconsistent structures predicted by large language models. We instantiated this framework on two structured prediction tasks, and five datasets. Across all cases, our results show that enforcing consistency not only constructs structurally valid outputs, but also improves performance over the unconstrained variants.


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Verifying Annotation Agreement without Multiple Experts: A Case Study with Gujarati SNACS
Maitrey Mehta | Vivek Srikumar
Findings of the Association for Computational Linguistics: ACL 2023

Good datasets are a foundation of NLP research, and form the basis for training and evaluating models of language use. While creating datasets, the standard practice is to verify the annotation consistency using a committee of human annotators. This norm assumes that multiple annotators are available, which is not the case for highly specialized tasks or low-resource languages. In this paper, we ask: Can we evaluate the quality of a dataset constructed by a single human annotator? To address this question, we propose four weak verifiers to help estimate dataset quality, and outline when each may be employed. We instantiate these strategies for the task of semantic analysis of adpositions in Gujarati, a low-resource language, and show that our weak verifiers concur with a double-annotation study. As an added contribution, we also release the first dataset with semantic annotations in Gujarati along with several model baselines.


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Psychotherapy is Not One Thing: Simultaneous Modeling of Different Therapeutic Approaches
Maitrey Mehta | Derek Caperton | Katherine Axford | Lauren Weitzman | David Atkins | Vivek Srikumar | Zac Imel
Proceedings of the Eighth Workshop on Computational Linguistics and Clinical Psychology

There are many different forms of psychotherapy. Itemized inventories of psychotherapeutic interventions provide a mechanism for evaluating the quality of care received by clients and for conducting research on how psychotherapy helps. However, evaluations such as these are slow, expensive, and are rarely used outside of well-funded research studies. Natural language processing research has progressed to allow automating such tasks. Yet, NLP work in this area has been restricted to evaluating a single approach to treatment, when prior research indicates therapists used a wide variety of interventions with their clients, often in the same session. In this paper, we frame this scenario as a multi-label classification task, and develop a group of models aimed at predicting a wide variety of therapist talk-turn level orientations. Our models achieve F1 macro scores of 0.5, with the class F1 ranging from 0.36 to 0.67. We present analyses which offer insights into the capability of such models to capture psychotherapy approaches, and which may complement human judgment.


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INFOTABS: Inference on Tables as Semi-structured Data
Vivek Gupta | Maitrey Mehta | Pegah Nokhiz | Vivek Srikumar
Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics

In this paper, we observe that semi-structured tabulated text is ubiquitous; understanding them requires not only comprehending the meaning of text fragments, but also implicit relationships between them. We argue that such data can prove as a testing ground for understanding how we reason about information. To study this, we introduce a new dataset called INFOTABS, comprising of human-written textual hypotheses based on premises that are tables extracted from Wikipedia info-boxes. Our analysis shows that the semi-structured, multi-domain and heterogeneous nature of the premises admits complex, multi-faceted reasoning. Experiments reveal that, while human annotators agree on the relationships between a table-hypothesis pair, several standard modeling strategies are unsuccessful at the task, suggesting that reasoning about tables can pose a difficult modeling challenge.

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Learning Constraints for Structured Prediction Using Rectifier Networks
Xingyuan Pan | Maitrey Mehta | Vivek Srikumar
Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics

Various natural language processing tasks are structured prediction problems where outputs are constructed with multiple interdependent decisions. Past work has shown that domain knowledge, framed as constraints over the output space, can help improve predictive accuracy. However, designing good constraints often relies on domain expertise. In this paper, we study the problem of learning such constraints. We frame the problem as that of training a two-layer rectifier network to identify valid structures or substructures, and show a construction for converting a trained network into a system of linear constraints over the inference variables. Our experiments on several NLP tasks show that the learned constraints can improve the prediction accuracy, especially when the number of training examples is small.


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A Logic-Driven Framework for Consistency of Neural Models
Tao Li | Vivek Gupta | Maitrey Mehta | Vivek Srikumar
Proceedings of the 2019 Conference on Empirical Methods in Natural Language Processing and the 9th International Joint Conference on Natural Language Processing (EMNLP-IJCNLP)

While neural models show remarkable accuracy on individual predictions, their internal beliefs can be inconsistent across examples. In this paper, we formalize such inconsistency as a generalization of prediction error. We propose a learning framework for constraining models using logic rules to regularize them away from inconsistency. Our framework can leverage both labeled and unlabeled examples and is directly compatible with off-the-shelf learning schemes without model redesign. We instantiate our framework on natural language inference, where experiments show that enforcing invariants stated in logic can help make the predictions of neural models both accurate and consistent.