Guiding Zero-Shot Paraphrase Generation with Fine-Grained Control Tokens

26410

Authors

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Abstract

AbstractSequence-to-sequence paraphrase generation models often struggle with the generation of diverse paraphrases. This deficiency constrains the viability of leveraging paraphrase generation in different Natural Language Processing tasks. We propose a translation-based guided paraphrase generation model that learns useful features for promoting surface form variation in generated paraphrases from cross-lingual parallel data. Our proposed method leverages multilingual neural machine translation pretraining to learn zero-shot paraphrasing. Furthermore, we incorporate dedicated prefix tokens into the training of the machine translation models to promote variation. The prefix tokens are designed to affect various linguistic features related to surface form realizations, and can be applied during inference to guide the decoding process towards a desired solution. We assess the proposed guided model on paraphrase generation in three languages, English, Finnish, and Swedish, and provide analysis on the feasibility of the prefix tokens to guided paraphrasing. Our analysis suggests that the attributes represented by the prefix tokens are useful in promoting variation, by pushing the paraphrases generated by the guided model to diverge from the input sentence while preserving semantics conveyed by the sentence well.

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Proceedings of the The 12th Joint Conference on Lexical and Computational Semantics (*SEM 2023), pages 11–17 July 13-14, 2023 ©2023 Association for Computational Linguistics Leverage Points in Modality Shifts: Comparing Language-only and Multimodal Word Representations Aleksey Tikhonov Inworld.AI altsoph@gmail.com Lisa Bylinina∗ Center for Language and Cognition University of Groningen e.g.bylinina@rug.nl Denis Paperno∗ Institute for Language Sciences Utrecht University d.paperno@uu.nl Abstract Multimodal embeddings aim to enrich the se- mantic information in neural representations of language compared to text-only models. While different embeddings exhibit different applica- bility and performance on downstream tasks, little is known about the systematic representa- tion differences attributed to the visual modal- ity. Our paper compares word embeddings from three vision-and-language models (CLIP, OpenCLIP and Multilingual CLIP, Radford et al. 2021; Ilharco et al. 2021; Carlsson et al. 2022) and three text-only models, with static (FastText, Bojanowski et al., 2017) as well as contextual representations (multilingual BERT Devlin et al. 2018; XLM-RoBERTa, Conneau et al. 2019). This is the first large-scale study of the effect of visual grounding on language rep- resentations, including 46 semantic parameters. We identify meaning properties and relations that characterize words whose embeddings are most affected by the inclusion of visual modal- ity in the training data; that is, points where visual grounding turns out most important. We find that the effect of visual modality correlates most with denotational semantic properties re- lated to concreteness, but is also detected for several specific semantic classes, as well as for valence, a sentiment-related connotational property of linguistic expressions. 1 Introduction Linguistic representations developed by recent large pre-trained language models (LMs) (Devlin et al., 2018; Liu et al., 2019; Radford et al., 2019 a.o.) proved to be very useful across a variety of practical applications. This success has given a new life to the debate around extractability and quality of semantic information in representations trained solely on textual input. According to the ∗Equal contribution. widely supported argument, unless the textual data is grounded in a separate space (say, visual), the lin- guistic representations are bound to be semantically deficient (see Bender and Koller, 2020 a.o.). We aim to shed new empirical light on the dis- cussion of grounding in computational models by comparing language-only text representations to visually informed text representations. Recent advances produced empirically successful large models pre-trained on a combination of textual and visual data (Li et al., 2019; Tan and Bansal, 2019, 2020; Radford et al., 2021). While these multimodal systems have already given rise to a plethora of applications for language-and-vision (L&V) downstream tasks, there is still little work that directly compares textual representations of language-only models to those of multimodal ones (however, see Davis et al., 2019; Lüddecke et al., 2019; Pezzelle et al., 2021). In contrast to previous related work that focuses on model evaluation with respect to specific benchmarks, we look at the im- pact of visual grounding from a somewhat different, non-evaluation-based perspective. We do not aim to measure the representation quality with respect to some gold standard, but …

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Labeled Text

AbstractSequence-to-sequence paraphrase generation models often struggle with the generation of diverse paraphrases. This deficiency constrains the viability of leveraging paraphrase generation in different Natural Language Processing tasks. We propose a translation-based guided paraphrase generation model that learns useful features for promoting surface form variation in generated paraphrases from cross-lingual parallel data. Our proposed method leverages multilingual neural machine translation pretraining to learn zero-shot paraphrasing. Furthermore, we incorporate dedicated prefix tokens into the training of the machine translation models to promote variation. The prefix tokens are designed to affect various linguistic features related to surface form realizations, and can be applied during inference to guide the decoding process towards a desired solution. We assess the proposed guided model on paraphrase generation in three languages, English, Finnish, and Swedish, and provide analysis on the feasibility of the prefix tokens to guided paraphrasing. Our analysis suggests that the attributes represented by the prefix tokens are useful in promoting variation, by pushing the paraphrases generated by the guided model to diverge from the input sentence while preserving semantics conveyed by the sentence well.

Publication Details

Paper ID:
26410
Year:
2023
Publication:
TIPSTER
Publication Type:
conf
DOI:
nan