Hanna Suominen


2023

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TextSimplifier: A Modular, Extensible, and Context Sensitive Simplification Framework for Improved Natural Language Understanding
Sandaru Seneviratne | Eleni Daskalaki | Hanna Suominen
Proceedings of the Second Workshop on Text Simplification, Accessibility and Readability

Natural language understanding is fundamental to knowledge acquisition in today’s information society. However, natural language is often ambiguous with frequent occurrences of complex terms, acronyms, and abbreviations that require substitution and disambiguation, for example, by “translation” from complex to simpler text for better understanding. These tasks are usually difficult for people with limited reading skills, second language learners, and non-native speakers. Hence, the development of text simplification systems that are capable of simplifying complex text is of paramount importance. Thus, we conducted a user study to identify which components are essential in a text simplification system. Based on our findings, we proposed an improved text simplification framework, covering a broader range of aspects related to lexical simplification — from complexity identification to lexical substitution and disambiguation — while supplementing the simplified outputs with additional information for better understandability. Based on the improved framework, we developed TextSimplifier, a modularised, context-sensitive, end-to-end simplification framework, and engineered its web implementation. This system targets lexical simplification that identifies complex terms and acronyms followed by their simplification through substitution and disambiguation for better understanding of complex language.

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A Quest for Paradigm Coverage: The Story of Nen
Saliha Muradoglu | Hanna Suominen | Nicholas Evans
Proceedings of the Second Workshop on NLP Applications to Field Linguistics

Language documentation aims to collect a representative corpus of the language. Nevertheless, the question of how to quantify the comprehensive of the collection persists. We propose leveraging computational modelling to provide a supplementary metric to address this question in a low-resource language setting. We apply our proposed methods to the Papuan language Nen. Nen is actively in the process of being described and documented. Given the enormity of the task of language documentation, we focus on one subdomain, namely Nen verbal morphology. This study examines four verb types: copula, positional, middle, and transitive. We propose model-based paradigm generation for each verb type as a new way to measure completeness, where accuracy is analogous to the coverage of the paradigm. We contrast the paradigm attestation within the corpus (constructed from fieldwork data) and the accuracy of the paradigm generated by Transformer models trained for inflection. This analysis is extended by extrapolating from the learning curve established to provide predictions for the quantity of data required to generate a complete paradigm correctly. We also explore the correlation between high-frequency morphosyntactic features and model accuracy. We see a positive correlation between high-frequency feature combinations and model accuracy, but this is only sometimes the case. We also see high accuracy for low-frequency morphosyntactic features. Our results show that model coverage is significantly higher for the middle and transitive verbs but not the positional verb. This is an interesting finding, as the positional verb paradigm is the smallest of the four.

2022

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m-Networks: Adapting the Triplet Networks for Acronym Disambiguation
Sandaru Seneviratne | Elena Daskalaki | Artem Lenskiy | Hanna Suominen
Proceedings of the 4th Clinical Natural Language Processing Workshop

Acronym disambiguation (AD) is the process of identifying the correct expansion of the acronyms in text. AD is crucial in natural language understanding of scientific and medical documents due to the high prevalence of technical acronyms and the possible expansions. Given that natural language is often ambiguous with more than one meaning for words, identifying the correct expansion for acronyms requires learning of effective representations for words, phrases, acronyms, and abbreviations based on their context. In this paper, we proposed an approach to leverage the triplet networks and triplet loss which learns better representations of text through distance comparisons of embeddings. We tested both the triplet network-based method and the modified triplet network-based method with m networks on the AD dataset from the SDU@AAAI-21 AD task, CASI dataset, and MeDAL dataset. F scores of 87.31%, 70.67%, and 75.75% were achieved by the m network-based approach for SDU, CASI, and MeDAL datasets respectively indicating that triplet network-based methods have comparable performance but with only 12% of the number of parameters in the baseline method. This effective implementation is available at https://github.com/sandaruSen/m_networks under the MIT license.

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CILS at TSAR-2022 Shared Task: Investigating the Applicability of Lexical Substitution Methods for Lexical Simplification
Sandaru Seneviratne | Elena Daskalaki | Hanna Suominen
Proceedings of the Workshop on Text Simplification, Accessibility, and Readability (TSAR-2022)

Lexical simplification — which aims to simplify complex text through the replacement of difficult words using simpler alternatives while maintaining the meaning of the given text — is popular as a way of improving text accessibility for both people and computers. First, lexical simplification through substitution can improve the understandability of complex text for, for example, non-native speakers, second language learners, and people with low literacy. Second, its usefulness has been demonstrated in many natural language processing problems like data augmentation, paraphrase generation, or word sense induction. In this paper, we investigated the applicability of existing unsupervised lexical substitution methods based on pre-trained contextual embedding models and WordNet, which incorporate Context Information, for Lexical Simplification (CILS). Although the performance of this CILS approach has been outstanding in lexical substitution tasks, its usefulness was limited at the TSAR-2022 shared task on lexical simplification. Consequently, a minimally supervised approach with careful tuning to a given simplification task may work better than unsupervised methods. Our investigation also encouraged further work on evaluating the simplicity of potential candidates and incorporating them into the lexical simplification methods.

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Scoping natural language processing in Indonesian and Malay for education applications
Zara Maxwell-Smith | Michelle Kohler | Hanna Suominen
Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics: Student Research Workshop

Indonesian and Malay are underrepresented in the development of natural language processing (NLP) technologies and available resources are difficult to find. A clear picture of existing work can invigorate and inform how researchers conceptualise worthwhile projects. Using an education sector project to motivate the study, we conducted a wide-ranging overview of Indonesian and Malay human language technologies and corpus work. We charted 657 included studies according to Hirschberg and Manning’s 2015 description of NLP, concluding that the field was dominated by exploratory corpus work, machine reading of text gathered from the Internet, and sentiment analysis. In this paper, we identify most published authors and research hubs, and make a number of recommendations to encourage future collaboration and efficiency within NLP in Indonesian and Malay.

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Pretrained Knowledge Base Embeddings for improved Sentential Relation Extraction
Andrea Papaluca | Daniel Krefl | Hanna Suominen | Artem Lenskiy
Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics: Student Research Workshop

In this work we put forward to combine pretrained knowledge base graph embeddings with transformer based language models to improve performance on the sentential Relation Extraction task in natural language processing. Our proposed model is based on a simple variation of existing models to incorporate off-task pretrained graph embeddings with an on-task finetuned BERT encoder. We perform a detailed statistical evaluation of the model on standard datasets. We provide evidence that the added graph embeddings improve the performance, making such a simple approach competitive with the state-of-the-art models that perform explicit on-task training of the graph embeddings. Furthermore, we ob- serve for the underlying BERT model an interesting power-law scaling behavior between the variance of the F1 score obtained for a relation class and its support in terms of training examples.

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Automatic Gloss Dictionary for Sign Language Learners
Chenchen Xu | Dongxu Li | Hongdong Li | Hanna Suominen | Ben Swift
Proceedings of the 60th Annual Meeting of the Association for Computational Linguistics: System Demonstrations

A multi-language dictionary is a fundamental tool for language learning, allowing the learner to look up unfamiliar words. Searching an unrecognized word in the dictionary does not usually require deep knowledge of the target language. However, this is not true for sign language, where gestural elements preclude this type of easy lookup. This paper introduces GlossFinder, an online tool supporting 2, 000 signs to assist language learners in determining the meaning of given signs. Unlike alternative systems of complex inputs, our system requires only that learners imitate the sign in front of a standard webcam. A user study conducted among sign language speakers of varying ability compared our system against existing alternatives and the interviews indicated a clear preference for our new system. This implies that GlossFinder can lower the barrier in sign language learning by addressing the common problem of sign finding and make it accessible to the wider community.

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CILex: An Investigation of Context Information for Lexical Substitution Methods
Sandaru Seneviratne | Elena Daskalaki | Artem Lenskiy | Hanna Suominen
Proceedings of the 29th International Conference on Computational Linguistics

Lexical substitution, which aims to generate substitutes for a target word given a context, is an important natural language processing task useful in many applications. Due to the paucity of annotated data, existing methods for lexical substitution tend to rely on manually curated lexical resources and contextual word embedding models. Methods based on lexical resources are likely to miss relevant substitutes whereas relying only on contextual word embedding models fails to provide adequate information on the impact of a substitute in the entire context and the overall meaning of the input. We proposed CILex, which uses contextual sentence embeddings along with methods that capture additional context information complimenting contextual word embeddings for lexical substitution. This ensured the semantic consistency of a substitute with the target word while maintaining the overall meaning of the sentence. Our experimental comparisons with previously proposed methods indicated that our solution is now the state-of-the-art on both the widely used LS07 and CoInCo datasets with P@1 scores of 55.96% and 57.25% for lexical substitution. The implementation of the proposed approach is available at https://github.com/sandaruSen/CILex under the MIT license.

2021

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An Approach to the Frugal Use of Human Annotators to Scale up Auto-coding for Text Classification Tasks
Li’An Chen | Hanna Suominen
Proceedings of the 19th Annual Workshop of the Australasian Language Technology Association

Human annotation for establishing the training data is often a very costly process in natural language processing (NLP) tasks, which has led to frugal NLP approaches becoming an important research topic. Many research teams struggle to complete projects with limited funding, labor, and computational resources. Driven by the Move-Step analytic framework theorized in the applied linguistics field, our study offers a rigorous approach to the frugal use of two human annotators to scale up auto-coding for text classification tasks. We applied the Linear Support Vector Machine algorithm to text classification of a job ad corpus. Our Cohen’s Kappa for inter-rater agreement and Area Under the Curve (AUC) values reached averages of 0.76 and 0.80, respectively. The calculated time consumption for our human training process was 36 days. The results indicated that even the strategic and frugal use of only two human annotators could enable the efficient training of classifiers with reasonably good performance. This study does not aim to provide generalizability of the results. Rather, we propose that the annotation strategies arising from this study be considered by our readers only if such strategies are fit for one’s specific research purposes.

2020

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To compress or not to compress? A Finite-State approach to Nen verbal morphology
Saliha Muradoglu | Nicholas Evans | Hanna Suominen
Proceedings of the 58th Annual Meeting of the Association for Computational Linguistics: Student Research Workshop

This paper describes the development of a verbal morphological parser for an under-resourced Papuan language, Nen. Nen verbal morphology is particularly complex, with a transitive verb taking up to 1,740 unique features. The structural properties exhibited by Nen verbs raises interesting choices for analysis. Here we compare two possible methods of analysis: ‘Chunking’ and decomposition. ‘Chunking’ refers to the concept of collating morphological segments into one, whereas the decomposition model follows a more classical linguistic approach. Both models are built using the Finite-State Transducer toolkit foma. The resultant architecture shows differences in size and structural clarity. While the ‘Chunking’ model is under half the size of the full de-composed counterpart, the decomposition displays higher structural order. In this paper, we describe the challenges encountered when modelling a language exhibiting distributed exponence and present the first morphological analyser for Nen, with an overall accuracy of 80.3%.

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An Automatic Vowel Space Generator for Language Learner Pronunciation Acquisition and Correction
Xinyuan Chao | Charbel El-Khaissi | Nicholas Kuo | Priscilla Kan John | Hanna Suominen
Proceedings of the 18th Annual Workshop of the Australasian Language Technology Association

Speech visualisations are known to help language learners to acquire correct pronunciation and promote a better study experience. We present a two-step approach based on two established techniques to display tongue tip movements of an acoustic speech signal on a vowel space plot. First we use Energy Entropy Ratio to extract vowels; and then we apply Linear Predictive Coding root method to estimate Formant 1 and Formant 2. We invited and collected acoustic data from one Modern Standard Arabic (MSA) lecture and four MSA students. Our proof of concept was able to reflect differences between the tongue tip movements in a native MSA speaker to those of a MSA language learner. This paper addresses principle methods for generating features that reflect bio-physiological features of speech and thus, facilitates an approach that can be generally adapted to languages other than MSA.

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Transformer Semantic Parsing
Gabriela Ferraro | Hanna Suominen
Proceedings of the 18th Annual Workshop of the Australasian Language Technology Association

In neural semantic parsing, sentences are mapped to meaning representations using encoder-decoder frameworks. In this paper, we propose to apply the Transformer architecture, instead of recurrent neural networks, to this task. Experiments in two data sets from different domains and with different levels of difficulty show that our model achieved better results than strong baselines in certain settings and competitive results across all our experiments.

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Applications of Natural Language Processing in Bilingual Language Teaching: An Indonesian-English Case Study
Zara Maxwell-Smith | Simón González Ochoa | Ben Foley | Hanna Suominen
Proceedings of the Fifteenth Workshop on Innovative Use of NLP for Building Educational Applications

Multilingual corpora are difficult to compile and a classroom setting adds pedagogy to the mix of factors which make this data so rich and problematic to classify. In this paper, we set out methodological considerations of using automated speech recognition to build a corpus of teacher speech in an Indonesian language classroom. Our preliminary results (64% word error rate) suggest these tools have the potential to speed data collection in this context. We provide practical examples of our data structure, details of our piloted computer-assisted processes, and fine-grained error analysis. Our study is informed and directed by genuine research questions and discussion in both the education and computational linguistics fields. We highlight some of the benefits and risks of using these emerging technologies to analyze the complex work of language teachers and in education more generally.

2019

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PostAc : A Visual Interactive Search, Exploration, and Analysis Platform for PhD Intensive Job Postings
Chenchen Xu | Inger Mewburn | Will J Grant | Hanna Suominen
Proceedings of the 57th Annual Meeting of the Association for Computational Linguistics: System Demonstrations

Over 60% of Australian PhD graduates land their first job after graduation outside academia, but this job market remains largely hidden to these job seekers. Employers’ low awareness and interest in attracting PhD graduates means that the term “PhD” is rarely used as a keyword in job advertisements; 80% of companies looking to employ similar researchers do not specifically ask for a PhD qualification. As a result, typing in “PhD” to a job search engine tends to return mostly academic jobs. We set out to make the market for advanced research skills more visible to job seekers. In this paper, we present PostAc, an online platform of authentic job postings that helps PhD graduates sharpen their career thinking. The platform is underpinned by research on the key factors that identify what an employer is looking for when they want to hire a highly skilled researcher. Its ranking model leverages the free-form text embedded in the job description to quantify the most sought-after PhD skills and educate information seekers about the Australian job-market appetite for PhD skills. The platform makes visible the geographic location, industry sector, job title, working hours, continuity, and wage of the research intensive jobs. This is the first data-driven exploration in this field. Both empirical results and online platform will be presented in this paper.

2018

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The Importance of Recommender and Feedback Features in a Pronunciation Learning Aid
Dzikri Fudholi | Hanna Suominen
Proceedings of the 5th Workshop on Natural Language Processing Techniques for Educational Applications

Verbal communication — and pronunciation as its part — is a core skill that can be developed through guided learning. An artificial intelligence system can take a role in these guided learning approaches as an enabler of an application for pronunciation learning with a recommender system to guide language learners through exercises and feedback system to correct their pronunciation. In this paper, we report on a user study on language learners’ perceived usefulness of the application. 16 international students who spoke non-native English and lived in Australia participated. 13 of them said they need to improve their pronunciation skills in English because of their foreign accent. The feedback system with features for pronunciation scoring, speech replay, and giving a pronunciation example was deemed essential by most of the respondents. In contrast, a clear dichotomy between the recommender system perceived as useful or useless existed; the system had features to prompt new common words or old poorly-scored words. These results can be used to target research and development from information retrieval and reinforcement learning for better and better recommendations to speech recognition and speech analytics for accent acquisition.

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EPUTION at SemEval-2018 Task 2: Emoji Prediction with User Adaption
Liyuan Zhou | Qiongkai Xu | Hanna Suominen | Tom Gedeon
Proceedings of the 12th International Workshop on Semantic Evaluation

This paper describes our approach, called EPUTION, for the open trial of the SemEval- 2018 Task 2, Multilingual Emoji Prediction. The task relates to using social media — more precisely, Twitter — with its aim to predict the most likely associated emoji of a tweet. Our solution for this text classification problem explores the idea of transfer learning for adapting the classifier based on users’ tweeting history. Our experiments show that our user-adaption method improves classification results by more than 6 per cent on the macro-averaged F1. Thus, our paper provides evidence for the rationality of enriching the original corpus longitudinally with user behaviors and transferring the lessons learned from corresponding users to specific instances.

2016

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Pairwise FastText Classifier for Entity Disambiguation
Cheng Yu | Bing Chu | Rohit Ram | James Aichinger | Lizhen Qu | Hanna Suominen
Proceedings of the Australasian Language Technology Association Workshop 2016

2014

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Segmentation of patent claims for improving their readability
Gabriela Ferraro | Hanna Suominen | Jaume Nualart
Proceedings of the 3rd Workshop on Predicting and Improving Text Readability for Target Reader Populations (PITR)

2013

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Noise in Speech-to-Text Voice: Analysis of Errors and Feasibility of Phonetic Similarity for Their Correction
Hanna Suominen | Gabriela Ferraro
Proceedings of the Australasian Language Technology Association Workshop 2013 (ALTA 2013)

2010

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Characteristics and Analysis of Finnish and Swedish Clinical Intensive Care Nursing Narratives
Helen Allvin | Elin Carlsson | Hercules Dalianis | Riitta Danielsson-Ojala | Vidas Daudaravicius | Martin Hassel | Dimitrios Kokkinakis | Heljä Lundgren-Laine | Gunnar Nilsson | Øystein Nytrø | Sanna Salanterä | Maria Skeppstedt | Hanna Suominen | Sumithra Velupillai
Proceedings of the NAACL HLT 2010 Second Louhi Workshop on Text and Data Mining of Health Documents