研究論文

Findings - NAACL
2022
Yutong Shao, Nikita Bhutani, Sajjadur Rahman, Estevam Hruschka
Entity set expansion (ESE) aims at obtaining a more complete set of entities given a textual corpus and a seed set of entities of a concept. Although it is a critical task in many NLP applications, existing benchmarks are limited to well-formed text (e.g., Wikipedia) and well-defined concepts (e.g., countries and diseases). Furthermore, only a small number of predictions are evaluated compared to the actual size of an entity set. A rigorous assessment of ESE methods warrants more comprehensive benchmarks and evaluation. In this paper, we consider user-generated text to understand the generalizability of ESE methods. We develop new benchmarks and propose more rigorous evaluation metrics for assessing the performance of ESE methods. Additionally, we identify phenomena such as non-named entities, multifaceted entities, vague concepts that are more prevalent in user-generated text than well-formed text, and use them to profile ESE methods. We observe that the strong performance of state-of-the-art ESE methods does not generalize well to user-generated text. We conduct comprehensive empirical analysis and draw insights from the findings.
ACM SIGIR
2022
Reinald Kim Amplayo, Arthur Bražinskas, Yoshihiko Suhara, Xiaolan Wang, Bing Liu
Customer reviews are vital for making purchasing decisions in the Information Age. Such reviews can be automatically summarized to provide the user with an overview of opinions. In this tutorial, we present various aspects of opinion summarization that are useful for researchers and practitioners. First, we will introduce the task and major challenges. Then, we will present existing opinion summarization solutions, both pre-neural and neural. We will discuss how summarizers can be trained in the unsupervised, fewshot, and supervised regimes. Each regime has roots in different machine learning methods, such as auto-encoding, controllable text generation, and variational inference. Finally, we will discuss resources and evaluation methods and conclude with the future directions. This three-hour tutorial will provide a comprehensive overview over major advances in opinion summarization. The listeners will be well-equipped with the knowledge that is both useful for research and practical applications.
aiDM - SIGMOD
2022
Jin Wang, Yuliang Li, Wataru Hirota, Eser Kandogan
Real-world applications frequently seek to solve a general form of the Entity Matching (EM) problem to find associated entities. Such scenarios include matching jobs to candidates in job targeting, matching students with courses in online education, matching products with user reviews on e-commercial websites, and beyond. These tasks impose new requirements such as matching data entries with diverse formats or having a flexible and semantics-rich matching definition, which are beyond the current EM task formulation or approaches. In this paper, we introduce the problem of Generalized Entity Matching (GEM) that satisfies these practical requirements and presents an end-to-end pipeline Machop as the solution. Machop allows end users to define new matching tasks from scratch and apply them to new domains in a step-by-step manner. Machop cast the GEM problem as sequence pair classification so as to utilize the language understanding capability of Transformers-based language models (LMs) such as BERT. Moreover, it features a novel external knowledge injection approach with structure-aware pooling methods that allow domain experts to guide the LM to focus on the key matching information thus further contributing to the overall performance. Our experiments and case studies on real-world datasets from a popular recruiting platform show a significant 17.1% gain in F1 score against state-of-the-art methods along with meaningful matching results that are human understandable.
LREC
2022
Yuta Hayashibe
Often both an utterance and its context must be read to understand its intent in a dialog. Herein we propose a task, SelfContained Utterance Description (SCUD), to describe the intent of an utterance in a dialog with multiple simple natural sentences without the context. If a task can be performed concurrently with high accuracy as the conversation continues such as in an accommodation search dialog, the operator can easily suggest candidates to the customer by inputting SCUDs of the customer’s utterances to the accommodation search system. SCUDs can also describe the transition of customer requests from the dialog log. We construct a Japanese corpus to train and evaluate automatic SCUD generation. The corpus consists of 210 dialogs containing 10,814 sentences. We conduct an experiment to verify that SCUDs can be automatically generated. Additionally, we investigate the influence of the amount of training data on the automatic generation performance using 8,200 additional examples. https://github.com/megagonlabs/asdc
DEEM - SIGMOD
2022
Jin Wang, Yuliang Li
Entity Matching (EM) is an important problem in data integration and cleaning. More recently, deep learning techniques, especially pre-trained language models, have been integrated into EM applica- tions and achieved promising results. Unfortunately, the significant performance gain comes with the loss of explainability and trans- parency, deterring EM from the requirement of responsible data management. To address this issue, recent studies extended ex- plainable AI techniques to explain black-box EM models. However, these solutions have the major drawbacks that (i) their explana- tions do not capture the unique semantics characteristics of the EM problem; and (ii) they fail to provide an objective method to quantitatively evaluate the provided explanations. In this paper, we propose Minun, a model-agnostic method to generate expla- nations for EM solutions. We utilize counterfactual examples gen- erated from an EM customized search space as the explanations and develop two search algorithms to efficiently find such results. We also come up with a novel evaluation framework based on a student-teacher paradigm. The framework enables the evaluation of explanations of diverse formats by capturing the performance gain of a “student” model at simulating the target “teacher” model when explanations are given as side input. We conduct an extensive set of experiments on explaining state-of-the-art deep EM models on popular EM benchmark datasets. The results demonstrate that Minun significantly outperforms popular explainable AI methods such as LIME and SHAP on both explanation quality and scalability.
SIGMOD
2022
Yoshihiko Suhara, Jinfeng Li, Yuliang Li, Dan Zhang, Cagatay Demiralp, Chen Chen, Wang-Chiew Tan
Inferring meta-information about tables, such as column headers or relationships between columns, is an active research topic in data management as we find many tables are missing some of this information. In this paper, we study the problem of annotating table columns (i.e., predicting column types and the relationships between columns) using only information from the table itself. We develop a multi-task learning framework (called Doduo) based on pre-trained language models, which takes the entire table as input and predicts column types/relations using a single model. Experimental results show that Doduo establishes new state-of-the-art performance on two benchmarks for the column type prediction and column relation prediction tasks with up to 4.0% and 11.9% improvements, respectively. We report that Doduo can already outperform the previous state-of-the-art performance with a minimal number of tokens, only 8 tokens per column. We release a toolbox1 and confirm the effectiveness of Doduo on a real-world data science problem through a case study.
Findings - ACL
2022
Hayate Iso, Xiaolan Wang, Stefanos Angelidis, Yoshihiko Suhara
erating summaries that reflect popular subjective information expressed in multiple online reviews. While generated summaries offer general and concise information about a particular hotel or product, the information may be insufficient to help the user compare multiple different choices. Thus, the user may still struggle with the question “Which one should I pick?” In this paper, we propose the comparative opinion summarization task, which aims at generating two contrastive summaries and one common summary from two different candidate sets of reviews. We develop a comparative summarization framework CoCoSum, which consists of two base summarization models that jointly generate contrastive and common summaries. Experimental results on a newly created benchmark CoCoTrip show that CoCoSum can produce higher-quality contrastive and common summaries than state-of-the-art opinion summarization models.
CHI
2022
Sajjadur Rahman, Eser Kandogan
Information extraction (IE) approaches often play a pivotal role in text analysis and require significant human intervention. Therefore, a deeper understanding of existing IE practices and related challenges from a human-in-the-loop perspective is warranted. In this work, we conducted semi-structured interviews in an industrial environment and analyzed the reported IE approaches and limitations. We observed that data science workers often follow an iterative task model consisting of information foraging and sensemaking loops across all the phases of an IE workflow. The task model is generalizable and captures diverse goals across these phases (e.g., data preparation, modeling, evaluation.) We found several limitations in both foraging (e.g., data exploration) and sensemaking (e.g., qualitative debugging) loops stemming from a lack of adherence to existing cognitive engineering principles. Moreover, we identified that due to the iterative nature of an IE workflow, the requirement of provenance is often implied but rarely supported by existing systems. Based on these findings, we discuss design implications for supporting IE workflows and future research directions.
言語処理学会(NLP)
2022
林部祐太, Varga István
宿探し対話の自動応答に用いる知識整備として,ツリー構造での宿に関するトピックの整理に取り組んだ.トピック数(ノード数)は 791 個で,平均約8 個のトピック例文をアノテーションした.また,発話の解釈結果をツリーにマッピングして自動応答に活用することを想定し,ツリーへの自動分類にも取り組んだ.自動分類には,トピック数が非常に多いが学習事例が非常に少ないという制約においても頑健に動くよう,類似度に基づく手法を用いた.
言語処理学会(NLP)
2022
松田 寛, 大村舞(国立国語研究所), 浅原正幸 (国立国語研究所)
国語研の規程では,長単位は文節内部を自立語部分と付属語部分に分割する形で定義されるが,固有表現や複合辞・連語については個別の規則が適用される.また,長単位品詞は,短単位品詞の「名詞-普通名詞-副詞可能」「動詞-非自立可能」等の用法の曖昧性を,実際の文脈における用法で解決する必要がある.本研究では,Universal Dependencies に基づく依存構造解析モデルを拡張し,形態素解析器の短単位出力を長単位化する手法を評価した.同時に,用法に基づく 17 種の UPOS 推定結果,固有表現抽出結果,長単位末尾の形態素情報を組み合わせた長単位品詞判定規則を構築し,従来手法を上回る 97.2 ポイントの長単位品詞推定精度を得た.