Eiji Aramaki


2024

pdf bib
Assessing Authenticity and Anonymity of Synthetic User-generated Content in the Medical Domain
Tomohiro Nishiyama | Lisa Raithel | Roland Roller | Pierre Zweigenbaum | Eiji Aramaki
Proceedings of the Workshop on Computational Approaches to Language Data Pseudonymization (CALD-pseudo 2024)

Since medical text cannot be shared easily due to privacy concerns, synthetic data bears much potential for natural language processing applications. In the context of social media and user-generated messages about drug intake and adverse drug effects, this work presents different methods to examine the authenticity of synthetic text. We conclude that the generated tweets are untraceable and show enough authenticity from the medical point of view to be used as a replacement for a real Twitter corpus. However, original data might still be the preferred choice as they contain much more diversity.

2023

pdf bib
Comparative evaluation of boundary-relaxed annotation for Entity Linking performance
Gabriel Herman Bernardim Andrade | Shuntaro Yada | Eiji Aramaki
Proceedings of the 61st Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)

Entity Linking performance has a strong reliance on having a large quantity of high-quality annotated training data available. Yet, manual annotation of named entities, especially their boundaries, is ambiguous, error-prone, and raises many inconsistencies between annotators. While imprecise boundary annotation can degrade a model’s performance, there are applications where accurate extraction of entities’ surface form is not necessary. For those cases, a lenient annotation guideline could relieve the annotators’ workload and speed up the process. This paper presents a case study designed to verify the feasibility of such annotation process and evaluate the impact of boundary-relaxed annotation in an Entity Linking pipeline. We first generate a set of noisy versions of the widely used AIDA CoNLL-YAGO dataset by expanding the boundaries subsets of annotated entity mentions and then train three Entity Linking models on this data and evaluate the relative impact of imprecise annotation on entity recognition and disambiguation performances. We demonstrate that the magnitude of effects caused by noise in the Named Entity Recognition phase is dependent on both model complexity and noise ratio, while Entity Disambiguation components are susceptible to entity boundary imprecision due to strong vocabulary dependency.

2022

pdf bib
JaMIE: A Pipeline Japanese Medical Information Extraction System with Novel Relation Annotation
Fei Cheng | Shuntaro Yada | Ribeka Tanaka | Eiji Aramaki | Sadao Kurohashi
Proceedings of the Thirteenth Language Resources and Evaluation Conference

In the field of Japanese medical information extraction, few analyzing tools are available and relation extraction is still an under-explored topic. In this paper, we first propose a novel relation annotation schema for investigating the medical and temporal relations between medical entities in Japanese medical reports. We experiment with the practical annotation scenarios by separately annotating two different types of reports. We design a pipeline system with three components for recognizing medical entities, classifying entity modalities, and extracting relations. The empirical results show accurate analyzing performance and suggest the satisfactory annotation quality, the superiority of the latest contextual embedding models. and the feasible annotation strategy for high-accuracy demand.

pdf bib
Annotation-Scheme Reconstruction for “Fake News” and Japanese Fake News Dataset
Taichi Murayama | Shohei Hisada | Makoto Uehara | Shoko Wakamiya | Eiji Aramaki
Proceedings of the Thirteenth Language Resources and Evaluation Conference

Fake news provokes many societal problems; therefore, there has been extensive research on fake news detection tasks to counter it. Many fake news datasets were constructed as resources to facilitate this task. Contemporary research focuses almost exclusively on the factuality aspect of the news. However, this aspect alone is insufficient to explain “fake news,” which is a complex phenomenon that involves a wide range of issues. To fully understand the nature of each instance of fake news, it is important to observe it from various perspectives, such as the intention of the false news disseminator, the harmfulness of the news to our society, and the target of the news. We propose a novel annotation scheme with fine-grained labeling based on detailed investigations of existing fake news datasets to capture these various aspects of fake news. Using the annotation scheme, we construct and publish the first Japanese fake news dataset. The annotation scheme is expected to provide an in-depth understanding of fake news. We plan to build datasets for both Japanese and other languages using our scheme. Our Japanese dataset is published at https://hkefka385.github.io/dataset/fakenews-japanese/.

pdf bib
Emotion Analysis of Writers and Readers of Japanese Tweets on Vaccinations
Patrick John Ramos | Kiki Ferawati | Kongmeng Liew | Eiji Aramaki | Shoko Wakamiya
Proceedings of the 12th Workshop on Computational Approaches to Subjectivity, Sentiment & Social Media Analysis

Public opinion in social media is increasingly becoming a critical factor in pandemic control. Understanding the emotions of a population towards vaccinations and COVID-19 may be valuable in convincing members to become vaccinated. We investigated the emotions of Japanese Twitter users towards Tweets related to COVID-19 vaccination. Using the WRIME dataset, which provides emotion ratings for Japanese Tweets sourced from writers (Tweet posters) and readers, we fine-tuned a BERT model to predict levels of emotional intensity. This model achieved a training accuracy of MSE = 0.356. A separate dataset of 20,254 Japanese Tweets containing COVID-19 vaccine-related keywords was also collected, on which the fine-tuned BERT was used to perform emotion analysis. Afterwards, a correlation analysis between the extracted emotions and a set of vaccination measures in Japan was conducted.The results revealed that surprise and fear were the most intense emotions predicted by the model for writers and readers, respectively, on the vaccine-related Tweet dataset. The correlation analysis also showed that vaccinations were weakly positively correlated with predicted levels of writer joy, writer/reader anticipation, and writer/reader trust.

pdf bib
PICO Corpus: A Publicly Available Corpus to Support Automatic Data Extraction from Biomedical Literature
Faith Mutinda | Kongmeng Liew | Shuntaro Yada | Shoko Wakamiya | Eiji Aramaki
Proceedings of the first Workshop on Information Extraction from Scientific Publications

We present a publicly available corpus with detailed annotations describing the core elements of clinical trials: Participants, Intervention, Control, and Outcomes. The corpus consists of 1011 abstracts of breast cancer randomized controlled trials extracted from the PubMed database. The corpus improves previous corpora by providing detailed annotations for outcomes to identify numeric texts that report the number of participants that experience specific outcomes. The corpus will be helpful for the development of systems for automatic extraction of data from randomized controlled trial literature to support evidence-based medicine. Additionally, we demonstrate the feasibility of the corpus by using two strong baselines for named entity recognition task. Most of the entities achieve F1 scores greater than 0.80 demonstrating the quality of the dataset.

2021

pdf bib
End-to-end Biomedical Entity Linking with Span-based Dictionary Matching
Shogo Ujiie | Hayate Iso | Shuntaro Yada | Shoko Wakamiya | Eiji Aramaki
Proceedings of the 20th Workshop on Biomedical Language Processing

Disease name recognition and normalization is a fundamental process in biomedical text mining. Recently, neural joint learning of both tasks has been proposed to utilize the mutual benefits. While this approach achieves high performance, disease concepts that do not appear in the training dataset cannot be accurately predicted. This study introduces a novel end-to-end approach that combines span representations with dictionary-matching features to address this problem. Our model handles unseen concepts by referring to a dictionary while maintaining the performance of neural network-based models. Experiments using two major datasaets demonstrate that our model achieved competitive results with strong baselines, especially for unseen concepts during training.

pdf bib
Mitigation of Diachronic Bias in Fake News Detection Dataset
Taichi Murayama | Shoko Wakamiya | Eiji Aramaki
Proceedings of the Seventh Workshop on Noisy User-generated Text (W-NUT 2021)

Fake news causes significant damage to society. To deal with these fake news, several studies on building detection models and arranging datasets have been conducted. Most of the fake news datasets depend on a specific time period. Consequently, the detection models trained on such a dataset have difficulty detecting novel fake news generated by political changes and social changes; they may possibly result in biased output from the input, including specific person names and organizational names. We refer to this problem as Diachronic Bias because it is caused by the creation date of news in each dataset. In this study, we confirm the bias, especially proper nouns including person names, from the deviation of phrase appearances in each dataset. Based on these findings, we propose masking methods using Wikidata to mitigate the influence of person names and validate whether they make fake news detection models robust through experiments with in-domain and out-of-domain data.

pdf bib
Are Metal Fans Angrier than Jazz Fans? A Genre-Wise Exploration of the Emotional Language of Music Listeners on Reddit
Vipul Mishra | Kongmeng Liew | Elena V. Epure | Romain Hennequin | Eiji Aramaki
Proceedings of the 2nd Workshop on NLP for Music and Spoken Audio (NLP4MusA)

2020

pdf bib
Towards a Versatile Medical-Annotation Guideline Feasible Without Heavy Medical Knowledge: Starting From Critical Lung Diseases
Shuntaro Yada | Ayami Joh | Ribeka Tanaka | Fei Cheng | Eiji Aramaki | Sadao Kurohashi
Proceedings of the Twelfth Language Resources and Evaluation Conference

Applying natural language processing (NLP) to medical and clinical texts can bring important social benefits by mining valuable information from unstructured text. A popular application for that purpose is named entity recognition (NER), but the annotation policies of existing clinical corpora have not been standardized across clinical texts of different types. This paper presents an annotation guideline aimed at covering medical documents of various types such as radiography interpretation reports and medical records. Furthermore, the annotation was designed to avoid burdensome requirements related to medical knowledge, thereby enabling corpus development without medical specialists. To achieve these design features, we specifically focus on critical lung diseases to stabilize linguistic patterns in corpora. After annotating around 1100 electronic medical records following the annotation scheme, we demonstrated its feasibility using an NER task. Results suggest that our guideline is applicable to large-scale clinical NLP projects.

pdf bib
Offensive Language Detection on Video Live Streaming Chat
Zhiwei Gao | Shuntaro Yada | Shoko Wakamiya | Eiji Aramaki
Proceedings of the 28th International Conference on Computational Linguistics

This paper presents a prototype of a chat room that detects offensive expressions in a video live streaming chat in real time. Focusing on Twitch, one of the most popular live streaming platforms, we created a dataset for the task of detecting offensive expressions. We collected 2,000 chat posts across four popular game titles with genre diversity (e.g., competitive, violent, peaceful). To make use of the similarity in offensive expressions among different social media platforms, we adopted state-of-the-art models trained on offensive expressions from Twitter for our Twitch data (i.e., transfer learning). We investigated two similarity measurements to predict the transferability, textual similarity, and game-genre similarity. Our results show that the transfer of features from social media to live streaming is effective. However, the two measurements show less correlation in the transferability prediction.

pdf bib
Classification of Nostalgic Music Through LDA Topic Modeling and Sentiment Analysis of YouTube Comments in Japanese Songs
Kongmeng Liew | Yukiko Uchida | Nao Maeura | Eiji Aramaki
Proceedings of the 1st Workshop on NLP for Music and Audio (NLP4MusA)

2019

pdf bib
Learning to Select, Track, and Generate for Data-to-Text
Hayate Iso | Yui Uehara | Tatsuya Ishigaki | Hiroshi Noji | Eiji Aramaki | Ichiro Kobayashi | Yusuke Miyao | Naoaki Okazaki | Hiroya Takamura
Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics

We propose a data-to-text generation model with two modules, one for tracking and the other for text generation. Our tracking module selects and keeps track of salient information and memorizes which record has been mentioned. Our generation module generates a summary conditioned on the state of tracking module. Our proposed model is considered to simulate the human-like writing process that gradually selects the information by determining the intermediate variables while writing the summary. In addition, we also explore the effectiveness of the writer information for generations. Experimental results show that our proposed model outperforms existing models in all evaluation metrics even without writer information. Incorporating writer information further improves the performance, contributing to content planning and surface realization.

2018

pdf bib
J-MeDic: A Japanese Disease Name Dictionary based on Real Clinical Usage
Kaoru Ito | Hiroyuki Nagai | Taro Okahisa | Shoko Wakamiya | Tomohide Iwao | Eiji Aramaki
Proceedings of the Eleventh International Conference on Language Resources and Evaluation (LREC 2018)

2017

pdf bib
Multivariate Linear Regression of Symptoms-related Tweets for Infectious Gastroenteritis Scale Estimation
Ryo Takeuchi | Hayate Iso | Kaoru Ito | Shoko Wakamiya | Eiji Aramaki
Proceedings of the International Workshop on Digital Disease Detection using Social Media 2017 (DDDSM-2017)

To date, various Twitter-based event detection systems have been proposed. Most of their targets, however, share common characteristics. They are seasonal or global events such as earthquakes and flu pandemics. In contrast, this study targets unseasonal and local disease events. Our system investigates the frequencies of disease-related words such as “nausea”,“chill”,and “diarrhea” and estimates the number of patients using regression of these word frequencies. Experiments conducted using Japanese 47 areas from January 2017 to April 2017 revealed that the detection of small and unseasonal event is extremely difficult (overall performance: 0.13). However, we found that the event scale and the detection performance show high correlation in the specified cases (in the phase of patient increasing or decreasing). The results also suggest that when 150 and more patients appear in a high population area, we can expect that our social sensors detect this outbreak. Based on these results, we can infer that social sensors can reliably detect unseasonal and local disease events under certain conditions, just as they can for seasonal or global events.

2016

pdf bib
MedNLPDoc: Japanese Shared Task for Clinical NLP
Eiji Aramaki | Yoshinobu Kano | Tomoko Ohkuma | Mizuki Morita
Proceedings of the Clinical Natural Language Processing Workshop (ClinicalNLP)

Due to the recent replacements of physical documents with electronic medical records (EMR), the importance of information processing in medical fields has been increased. We have been organizing the MedNLP task series in NTCIR-10 and 11. These workshops were the first shared tasks which attempt to evaluate technologies that retrieve important information from medical reports written in Japanese. In this report, we describe the NTCIR-12 MedNLPDoc task which is designed for more advanced and practical use for the medical fields. This task is considered as a multi-labeling task to a patient record. This report presents results of the shared task, discusses and illustrates remained issues in the medical natural language processing field.

pdf bib
Detecting Japanese Patients with Alzheimer’s Disease based on Word Category Frequencies
Daisaku Shibata | Shoko Wakamiya | Ayae Kinoshita | Eiji Aramaki
Proceedings of the Clinical Natural Language Processing Workshop (ClinicalNLP)

In recent years, detecting Alzheimer disease (AD) in early stages based on natural language processing (NLP) has drawn much attention. To date, vocabulary size, grammatical complexity, and fluency have been studied using NLP metrics. However, the content analysis of AD narratives is still unreachable for NLP. This study investigates features of the words that AD patients use in their spoken language. After recruiting 18 examinees of 53–90 years old (mean: 76.89), they were divided into two groups based on MMSE scores. The AD group comprised 9 examinees with scores of 21 or lower. The healthy control group comprised 9 examinees with a score of 22 or higher. Linguistic Inquiry and Word Count (LIWC) classified words were used to categorize the words that the examinees used. The word frequency was found from observation. Significant differences were confirmed for the usage of impersonal pronouns in the AD group. This result demonstrated the basic feasibility of the proposed NLP-based detection approach.

pdf bib
Forecasting Word Model: Twitter-based Influenza Surveillance and Prediction
Hayate Iso | Shoko Wakamiya | Eiji Aramaki
Proceedings of COLING 2016, the 26th International Conference on Computational Linguistics: Technical Papers

Because of the increasing popularity of social media, much information has been shared on the internet, enabling social media users to understand various real world events. Particularly, social media-based infectious disease surveillance has attracted increasing attention. In this work, we specifically examine influenza: a common topic of communication on social media. The fundamental theory of this work is that several words, such as symptom words (fever, headache, etc.), appear in advance of flu epidemic occurrence. Consequently, past word occurrence can contribute to estimation of the number of current patients. To employ such forecasting words, one can first estimate the optimal time lag for each word based on their cross correlation. Then one can build a linear model consisting of word frequencies at different time points for nowcasting and for forecasting influenza epidemics. Experimentally obtained results (using 7.7 million tweets of August 2012 – January 2016), the proposed model achieved the best nowcasting performance to date (correlation ratio 0.93) and practically sufficient forecasting performance (correlation ratio 0.91 in 1-week future prediction, and correlation ratio 0.77 in 3-weeks future prediction). This report is the first of the relevant literature to describe a model enabling prediction of future epidemics using Twitter.

2015

pdf bib
Who caught a cold ? - Identifying the subject of a symptom
Shin Kanouchi | Mamoru Komachi | Naoaki Okazaki | Eiji Aramaki | Hiroshi Ishikawa
Proceedings of the 53rd Annual Meeting of the Association for Computational Linguistics and the 7th International Joint Conference on Natural Language Processing (Volume 1: Long Papers)

pdf bib
Disease Event Detection based on Deep Modality Analysis
Yoshiaki Kitagawa | Mamoru Komachi | Eiji Aramaki | Naoaki Okazaki | Hiroshi Ishikawa
Proceedings of the ACL-IJCNLP 2015 Student Research Workshop

pdf bib
Location Name Disambiguation Exploiting Spatial Proximity and Temporal Consistency
Takashi Awamura | Daisuke Kawahara | Eiji Aramaki | Tomohide Shibata | Sadao Kurohashi
Proceedings of the third International Workshop on Natural Language Processing for Social Media

2013

pdf bib
Word in a Dictionary is used by Numerous Users
Eiji Aramaki | Sachiko Maskawa | Mai Miyabe | Mizuki Morita | Sachi Yasuda
Proceedings of the Sixth International Joint Conference on Natural Language Processing

pdf bib
The First Workshop on Natural Language Processing for Medical and Healthcare Fields
Eiji Aramaki | Mizuki Morita
The First Workshop on Natural Language Processing for Medical and Healthcare Fields

pdf bib
Incorporating Knowledge Resources to Enhance Medical Information Extraction
Yasuhide Miura | Tomoko Ohkuma | Hiroshi Masuichi | Emiko Yamada Shinohara | Eiji Aramaki | Kazuhiko Ohe
The First Workshop on Natural Language Processing for Medical and Healthcare Fields

pdf bib
Clinical Vocabulary and Clinical Finding Concepts in Medical Literature
Takashi Okumura | Eiji Aramaki | Yuka Tateisi
The First Workshop on Natural Language Processing for Medical and Healthcare Fields

pdf bib
Proper and Efficient Treatment of Anaphora and Long-Distance Dependency in Context-Free Grammar: An Experiment with Medical Text
Wailok Tam | Koiti Hasida | Yusuke Matsubara | Eiji Aramaki | Mai Miyabe | Motoyuki Takaai | Hirosi Uozaki
The First Workshop on Natural Language Processing for Medical and Healthcare Fields

2011

pdf bib
Twitter Catches The Flu: Detecting Influenza Epidemics using Twitter
Eiji Aramaki | Sachiko Maskawa | Mizuki Morita
Proceedings of the 2011 Conference on Empirical Methods in Natural Language Processing

2010

pdf bib
Adverse-Effect Relations Extraction from Massive Clinical Records
Yasuhide Miura | Eiji Aramaki | Tomoko Ohkuma | Masatsugu Tonoike | Daigo Sugihara | Hiroshi Masuichi | Kazuhiko Ohe
Proceedings of the Second Workshop on NLP Challenges in the Information Explosion Era (NLPIX 2010)

pdf bib
Using Various Features in Machine Learning to Obtain High Levels of Performance for Recognition of Japanese Notational Variants
Masahiro Kojima | Masaki Murata | Jun’ichi Kazama | Kow Kuroda | Atsushi Fujita | Eiji Aramaki | Masaaki Tsuchida | Yasuhiko Watanabe | Kentaro Torisawa
Proceedings of the 24th Pacific Asia Conference on Language, Information and Computation

2009

pdf bib
TEXT2TABLE: Medical Text Summarization System Based on Named Entity Recognition and Modality Identification
Eiji Aramaki | Yasuhide Miura | Masatsugu Tonoike | Tomoko Ohkuma | Hiroshi Mashuichi | Kazuhiko Ohe
Proceedings of the BioNLP 2009 Workshop

pdf bib
Fast Decoding and Easy Implementation: Transliteration as Sequential Labeling
Eiji Aramaki | Takeshi Abekawa
Proceedings of the 2009 Named Entities Workshop: Shared Task on Transliteration (NEWS 2009)

2008

pdf bib
Orthographic Disambiguation Incorporating Transliterated Probability
Eiji Aramaki | Takeshi Imai | Kengo Miyo | Kazuhiko Ohe
Proceedings of the Third International Joint Conference on Natural Language Processing: Volume-I

2007

pdf bib
Support vector machine based orthographic disambiguation
Eiji Aramaki | Takeshi Imai | Kengo Miyo | Kazuhiko Ohe
Proceedings of the 11th Conference on Theoretical and Methodological Issues in Machine Translation of Natural Languages: Papers

pdf bib
UTH: SVM-based Semantic Relation Classification using Physical Sizes
Eiji Aramaki | Takeshi Imai | Kengo Miyo | Kazuhiko Ohe
Proceedings of the Fourth International Workshop on Semantic Evaluations (SemEval-2007)

2005

pdf bib
Toward Medical Ontology using Natural Language Processing
Eiji Aramaki | Takeshi Imai | Masayo Kashiwagi | Masayuki Kajino | Kengo Miyo | Kazuhiko Ohe
Proceedings of OntoLex 2005 - Ontologies and Lexical Resources

pdf bib
Probabilistic Model for Example-based Machine Translation
Eiji Aramaki | Sadao Kurohashi | Hideki Kashioka | Naoto Kato
Proceedings of Machine Translation Summit X: Papers

Example-based machine translation (EBMT) systems, so far, rely on heuristic measures in retrieving translation examples. Such a heuristic measure costs time to adjust, and might make its algorithm unclear. This paper presents a probabilistic model for EBMT. Under the proposed model, the system searches the translation example combination which has the highest probability. The proposed model clearly formalizes EBMT process. In addition, the model can naturally incorporate the context similarity of translation examples. The experimental results demonstrate that the proposed model has a slightly better translation quality than state-of-the-art EBMT systems.

2004

pdf bib
Example-based machine translation using structural translation examples
Eiji Aramaki | Sadao Kurohashi
Proceedings of the First International Workshop on Spoken Language Translation: Evaluation Campaign

2003

pdf bib
Word Selection for EBMT based on Monolingual Similarity and Translation Confidence
Eiji Aramaki | Sadao Kurohashi | Hideki Kashioka | Hideki Tanaka
Proceedings of the HLT-NAACL 2003 Workshop on Building and Using Parallel Texts: Data Driven Machine Translation and Beyond

2001

pdf bib
Finding translation correspondences from parallel parsed corpus for example-based translation
Eiji Aramaki | Sadao Kurohashi | Satoshi Sato | Hideo Watanabe
Proceedings of Machine Translation Summit VIII

This paper describes a system for finding phrasal translation correspondences from parallel parsed corpus that are collections paired English and Japanese sentences. First, the system finds phrasal correspondences by Japanese-English translation dictionary consultation. Then, the system finds correspondences in remaining phrases by using sentences dependency structures and the balance of all correspondences. The method is based on an assumption that in parallel corpus most fragments in a source sentence have corresponding fragments in a target sentence.

2000

pdf bib
Finding Structural Correspondences from Bilingual Parsed Corpus for Corpus-based Translation
Hideo Watanabe | Sadao Kurohashi | Eiji Aramaki
COLING 2000 Volume 2: The 18th International Conference on Computational Linguistics

Search