Dr Anton Ragni
BEng, MEng, PhD
School of Computer Science
Senior Lecturer in Speech and Language Technologies
Assessments Lead
Member of the Speech and Hearing (SpandH) research group
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+44 114 222 1925
Full contact details
School of Computer Science
Regent Court (DCS)
211 Portobello
Sheffield
S1 4DP
- Profile
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Dr Anton Ragni is a Senior Lecturer in Speech and Language Processing in the School of Computer Science at the University of Sheffield.
He graduated with BEng and MEng degrees in Information Technology from the University of Tartu, Estonia, in 2005 and 2007 respectively. He was awarded his PhD from the University of Cambridge in 2013.
From 2005 to 2008, he underwent graduate training at the Nordic Graduate School of Language Technology and from 2007 to 2008, he was an intern in the Speech Technology Group, Toshiba Research Europe Ltd, UK. From 2013 to 2018 and from 2018 to 2019, he was a Research Associate and Senior Research Associate, respectively, in Speech Processing at the University of Cambridge.
His current research interest focuses on machine learning approaches for speech and language processing.
- Research interests
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Dr Anton Ragni's research interests include:
- Core automatic speech recognition
- Efficient and expressive speech synthesis
- Spoken Language Translation
- Information Retrieval
- Conversation Modelling
- Publications
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Books
Journal articles
- Energy-Based Models for Speech Synthesis. ICASSP 2024 - 2024 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), abs/2310.12765, 12667-12671.
- Increasing Context for Estimating Confidence Scores in Automatic Speech Recognition. IEEE/ACM Transactions on Audio, Speech, and Language Processing, 30, 1319-1329.
- Exploiting future word contexts in neural network language models for speech recognition. IEEE/ACM Transactions on Audio, Speech, and Language Processing, 27(9), 1444-1454. View this article in WRRO
- Improving interpretability and regularization in deep learning. IEEE/ACM Transactions on Audio, Speech, and Language Processing, 26(2), 256-265. View this article in WRRO
- Structured Log Linear Models for Noise Robust Speech Recognition. IEEE Signal Processing Letters, 17(11), 945-948.
Chapters
- Experiments with Cross-Language Speech Retrieval for Lower-Resource Languages, Information Retrieval Technology (pp. 145-157). Springer International Publishing
Conference proceedings papers
- Non-intrusive speech intelligibility prediction for hearing-impaired users using intermediate ASR features and human memory models. ICASSP 2024 - 2024 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Vol. 2024 (pp 306-310). Seoul, Korea, 14 April 2024 - 14 April 2024. View this article in WRRO
- Adapting pretrained models for adult to child voice conversion. 2023 31st European Signal Processing Conference (EUSIPCO) Proceedings (pp 271-275). Helsinki, Finland, 4 September 2023 - 4 September 2023. View this article in WRRO
- Leveraging Cross-Utterance Context For ASR Decoding. INTERSPEECH 2023, Vol. 2023-August (pp 1359-1363)
- View this article in WRRO
- Confidence Estimation for Black Box Automatic Speech Recognition Systems Using Lattice Recurrent Neural Networks. ICASSP 2020 - 2020 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 4 May 2020 - 8 May 2020.
- Bi-directional Lattice Recurrent Neural Networks for Confidence Estimation. ICASSP 2019 (pp 6755-6759), 12 May 2019 - 17 May 2019. View this article in WRRO
- Sequence teacher-student training of acoustic models for automatic free speaking language assessment. 2018 IEEE Spoken Language Technology Workshop (SLT). Athens, Greece, 18 December 2018 - 21 December 2018. View this article in WRRO
- Phonetic and graphemic systems for multi-genre broadcast transcription. 2018 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). Calgary, AB, Canada, 15 April 2018 - 20 April 2018. View this article in WRRO
- Active memory networks for language modeling. Proceedings of Interspeech 2018 (pp 3338-3342). Hyderabad, India, 2 September 2018 - 6 September 2018. View this article in WRRO
- Impact of ASR performance on free speaking language assessment. Interspeech 2018 (pp 1641-1645). Hyderabad, India, 2 September 2018 - 6 September 2018. View this article in WRRO
- Automatic speech recognition system development in the "wild". Interspeech 2018 (pp 2217-2221). Hyderabad, India, 2 September 2018 - 6 September 2018. View this article in WRRO
- Confidence Estimation and Deletion Prediction Using Bidirectional Recurrent Neural Networks. 2018 IEEE Spoken Language Technology Workshop (SLT), 18 December 2018 - 21 December 2018. View this article in WRRO
- Future word contexts in neural network language models. 2017 IEEE Automatic Speech Recognition and Understanding Workshop (ASRU). Okinawa, Japan, 16 December 2017 - 20 December 2017.
- Investigating bidirectional recurrent neural network language models for speech recognition. Proceedings of Interspeech 2017 (pp 269-273). Stockholm, Sweden, 20 August 2017 - 24 August 2017. View this article in WRRO
- Use of graphemic lexicons for spoken language assessment. Proceedings of Interspeech 2017 (pp 2774-2778). Stockholm, Sweden, 20 August 2017 - 24 August 2017. View this article in WRRO
- Low-resource speech recognition and keyword-spotting. Speech and Computer : 19th International Conference, SPECOM 2017 (pp 3-19). Hatfield, UK, 12 September 2017 - 16 September 2017. View this article in WRRO
- Incorporating uncertainty into deep learning for spoken language assessment. Proceedings of the 55th Annual Meeting of the Association for Computational Linguistics (Volume 2 : Short Papers). Vancouver, Canada, 30 July 2017 - 4 August 2017. View this article in WRRO
- Stimulated training for automatic speech recognition and keyword search in limited resource conditions. 2017 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp 4830-4834). New Orleans, LA, USA, 5 March 2017 - 9 March 2017. View this article in WRRO
- Morph-to-word transduction for accurate and efficient automatic speech recognition and keyword search. 2017 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp 5770-5774). New Orleans, LA, USA, 5 March 2017 - 9 March 2017. View this article in WRRO
- Recurrent neural network language models for keyword search. 2017 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp 5775-5779). New Orleans, LA, USA, 5 March 2017 - 9 March 2017. View this article in WRRO
- Multi-language neural network language models. Interspeech 2016. San Francisco, CA, USA, 8 September 2016 - 12 September 2016. View this article in WRRO
- Log-linear system combination using structured support vector machines. Interspeech 2016. San Francisco, CA, USA, 8 September 2016 - 12 September 2016. View this article in WRRO
- System combination with log-linear models. 2016 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). Shanghai, China, 20 March 2016 - 25 March 2016. View this article in WRRO
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- Unicode-based graphemic systems for limited resource languages. 2015 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP). Brisbane, QLD, Australia, 19 April 2015 - 24 April 2015. View this article in WRRO
- A language space representation for speech recognition. 2015 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp 4634-4638). Brisbane, QLD, Australia, 19 April 2015 - 24 April 2015. View this article in WRRO
- Structured discriminative models using deep neural-network features. 2015 IEEE Workshop on Automatic Speech Recognition and Understanding (ASRU), 13 December 2015 - 17 December 2015. View this article in WRRO
- Multilingual representations for low resource speech recognition and keyword search. 2015 IEEE Workshop on Automatic Speech Recognition and Understanding (ASRU), 13 December 2015 - 17 December 2015. View this article in WRRO
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- Investigation of unsupervised adaptation of DNN acoustic models with filter bank input. 2014 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP) (pp 6344-6348). Florence, Italy, 4 May 2014 - 9 May 2014. View this article in WRRO
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- Efficient decoding with generative score-spaces using the expectation semiring. 2013 IEEE International Conference on Acoustics, Speech and Signal Processing, 26 May 2013 - 31 May 2013. View this article in WRRO
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- View this article in WRRO
- Inference algorithms for generative score-spaces. 2012 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 25 March 2012 - 30 March 2012. View this article in WRRO
- Derivative kernels for noise robust ASR. 2011 IEEE Workshop on Automatic Speech Recognition & Understanding, 11 December 2011 - 15 December 2011. View this article in WRRO
- Structured discriminative models for noise robust continuous speech recognition. 2011 IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), 22 May 2011 - 27 May 2011. View this article in WRRO
- Support vector machines for noise robust ASR. 2009 IEEE Workshop on Automatic Speech Recognition & Understanding, 13 November 2009 - 17 December 2009. View this article in WRRO
- View this article in WRRO
- How Much Context Does My Attention-Based ASR System Need?. Interspeech 2024 (pp 217-221)
- Learning from memory-based models. Interspeech 2024 (pp 2360-2364)
- View this article in WRRO
- An attention based model for off-topic spontaneous spoken response detection: An Initial Study. 7th ISCA Workshop on Speech and Language Technology in Education View this article in WRRO
- Rapid nonlinear speaker adaptation for large-vocabulary continuous speech recognition. Interspeech 2012
Preprints
- Foundation Models for Music: A Survey, arXiv.
- Self-Train Before You Transcribe, arXiv.
- Training Data Augmentation for Dysarthric Automatic Speech Recognition by Text-to-Dysarthric-Speech Synthesis, arXiv.
- Non-Intrusive Speech Intelligibility Prediction for Hearing-Impaired Users using Intermediate ASR Features and Human Memory Models, arXiv.
- How Much Context Does My Attention-Based ASR System Need?.
- Energy-Based Models For Speech Synthesis, arXiv.
- On the Effectiveness of Speech Self-supervised Learning for Music, arXiv.
- Leveraging Cross-Utterance Context For ASR Decoding, arXiv.
- MARBLE: Music Audio Representation Benchmark for Universal Evaluation, arXiv.
- MAP-Music2Vec: A Simple and Effective Baseline for Self-Supervised Music Audio Representation Learning..
- HERB: Measuring Hierarchical Regional Bias in Pre-trained Language Models, arXiv.
- Approximate Fixed-Points in Recurrent Neural Networks, arXiv.
- Continuous representations of intents for dialogue systems, arXiv.
- Confidence Estimation for Black Box Automatic Speech Recognition Systems Using Lattice Recurrent Neural Networks, arXiv.
- Bi-Directional Lattice Recurrent Neural Networks for Confidence Estimation, arXiv.
- Confidence Estimation and Deletion Prediction Using Bidirectional Recurrent Neural Networks, arXiv.
- Phonetic and Graphemic Systems for Multi-Genre Broadcast Transcription, arXiv.
- Future Word Contexts in Neural Network Language Models, arXiv.
- Grants
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Research Grants
- Exemplar-based Expressive Speech Synthesis, EPSRC, 06/2021 - 11/2023, £218,290, as PI
- Automatic voice conversion for transforming professional adult voice actors to artificial child voice actors, Innovate UK, 01/2021 - 01/2023, £173,605, as Co-PI
- Professional activities and memberships
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He is a member of IEEE, ISCA and a regular reviewer of major speech and machine learning journals and conferences.
Since 2016, he has been an Officer of ISCA Special Interest Group on Machine Learning in Speech and Language Processing. He received the Best Student Paper Award at the IEEE Workshop on Automatic Speech Recognition and Understanding for his paper “Generative kernels for noise robust ASR” co-authored with M. J. F. Gales in 2011.