Dr Ash Rahimi

Lecturer in Computer Science

School of Information Technology and Electrical Engineering
Faculty of Engineering, Architecture and Information Technology

Overview

Dr. Ash (Afshin) Rahimi is a lectuer at the School of Information Technology and Electrical Engineering, University of Queensland. He received his B.S. degree in computer science and M.S. degree in computational linguistics both from Sharif University of technology, Tehran, Iran, in 2006 and 2013, respectively. He achieved his PhD from The University of Melbourne in 2018 supervised by Timothy Baldwin and Trevor Cohn, focusing on social media user location inference from text and graph data. As a research fellow in 2019, he worked on NLP for low-resource languages, and also NLP in health domain. He regularly publishes his research results in top NLP conferences such as ACL, EMNLP, and NAACL (gScholar).

Research Interests

  • NLP, Social Media, Health
    My research interests fall within the fields of Natural Language Processing, Social Network Analysis and Machine Learning. I am specifically interested in exploiting both structured and unstructured data to help machines understand conversational language in Emergency Situations and Health Informatics.
  • Social Media Analysis and User Privacy
    Example project: Protecting Private Information in Public Domain: Defending Against Attribute Inference Helping social media users keep their attributes such as location private by building explainable attribute inference models. The models will be able to explain to the user why they're able to identify their private attributes e.g. by a post on Twitter or their follower list.
  • NLP for Low-resource Languages
    Building NLP models for low-resource languages where we don't have enough annotated training data through transfer learning techniques. Example project: In few years, most devices will be voice-operated, but support will be missing for low-resource languages such as indigenous languages of Australia. It is vital to create minimal support for these languages to have an inclusive society. One example of such methods is to build spoken language identification methods that work with limited annotated speech examples so that a device can at least have a backup strategy for speakers of these languages e.g. reply back in the identified language "Unfortunately, we don't support your language".
  • NLP for Health Domain
    Example project: Mapping public knowledge-bases such as WikiData to specialised knowledge-bases such as UMLS (a medical knowledge-base) to help patients understand medical terms. Assume a patient getting a discharge summary full of complex medical terms and difficult to understand through Google search. It'd be great if these terms could be linked to a publicly accessible knowledge source such as Wikipedia.

Qualifications

  • Docotor of Philosophy, The University of Melbourne

Publications

  • Rahimi, Afshin, Li, Yuan and Cohn, Trevor (2019). Massively multilingual transfer for NER. In: A. Korhonen, D. Traum and L. Marquez, 57th Annual Meeting of the Association for Computational Linguistics (ACL 2019). 57th Annual Meeting of the Association for Computational Linguistics (ACL), Florence, Italy, (151-164). Jul 28-Aug 02, 2019.

  • Hovy, Dirk, Rahimi, Afshin, Baldwin, Timothy and Brooke, Julian (2019). Visualizing regional language variation across Europe on Twitter. In Stanley D Brunn and Roland Kehrein (Ed.), Handbook of the Changing World Language Map () Cham, Switzerland: Springer International Publishing. doi:10.1007/978-3-319-73400-2_175-1

  • Darwish, Kareem, Magdy, Walid, Rahimi, Afshin, Baldwin, Timothy and Abokhodair, Norah (2018) Predicting online islamophobic behavior after #ParisAttacks. Journal of Web Science, 4 2: 34-52. doi:10.1561/106.00000013

View all Publications

Publications

Book Chapter

  • Hovy, Dirk, Rahimi, Afshin, Baldwin, Timothy and Brooke, Julian (2019). Visualizing regional language variation across Europe on Twitter. In Stanley D Brunn and Roland Kehrein (Ed.), Handbook of the Changing World Language Map () Cham, Switzerland: Springer International Publishing. doi:10.1007/978-3-319-73400-2_175-1

Journal Article

Conference Publication

  • Rahimi, Afshin, Li, Yuan and Cohn, Trevor (2019). Massively multilingual transfer for NER. In: A. Korhonen, D. Traum and L. Marquez, 57th Annual Meeting of the Association for Computational Linguistics (ACL 2019). 57th Annual Meeting of the Association for Computational Linguistics (ACL), Florence, Italy, (151-164). Jul 28-Aug 02, 2019.

  • Rahimi, Afshin, Cohn, Trevor and Baldwin, Timothy (2018). Semi-supervised User Geolocation via Graph Convolutional Networks. In: I. Gurevych and Y. Miyao, Proceedings of the 56th Annual Meeting of the Association for Computational Linguistics (Acl), Vol 1. 56th Annual Meeting of the Association for Computational Linguistics (ACL), Melbourne, Australia, (2009-2019). 15-20 July, 2018.

  • Miyazaki, Taro, Rahimi, Afshin, Cohn, Trevor and Baldwin, Timothy (2018). Twitter geolocation using knowledge-based methods. In: Proceedings of the 2018 EMNLP Workshop W-NUT: The 4th Workshop on Noisy User-generated Text. 2018 EMNLP Workshop W-NUT: The 4th Workshop on Noisy User-generated Text, Brussels, Belgium, (7-16). November 2018. doi:10.18653/v1/w18-6102

  • Rahimi, Afshin, Cohn, Trevor and Baldwin, Timothy (2017). A neural model for user geolocation and lexical dialectology. In: R. Barzilay and M.Y. Kan, Proceedings of the 55Th Annual Meeting of the Association for Computational Linguistics (Acl 2017), Vol 2. 55th Annual Meeting of the Association for Computational Linguistics (ACL), Vancouver, Canada, (209-216). 30 July - 4 August, 2017. doi:10.18653/v1/p17-2033

  • Rahimi, Afshin, Baldwin, Timothy and Cohn, Trevor (2017). Continuous representation of location for geolocation and lexical dialectology using mixture density networks. In: Proceedings of the 2017 Conference on Empirical Methods in Natural Language Processing. 2017 Conference on Empirical Methods in Natural Language Processing, Copenhagen, Denmark, (). September 2017. doi:10.18653/v1/d17-1016

  • Magdy, Walid, Darwish, Kareem, Abokhodair, Norah, Rahimi, Afshin and Baldwin, Timothy (2016). #ISISisNotIslam or #DeportAllMuslims? Predicting unspoken views. In: , , (95-106). . doi:10.1145/2908131.2908150

  • Rahimi, Afshin, Cohn, Trevor and Baldwin, Timothy (2016). Pigeo: A Python geotagging tool. In: 54th Annual Meeting of the Association for Computational Linguistics, ACL 2016 - System Demonstrations. 54th Annual Meeting of the Association for Computational Linguistics, ACL 2016, Berlin, Germany, (127-132). 7 - 12 August 2016.

  • Rahimi, Afshin, Vu, Duy, Cohn, Trevor and Baldwin, Timothy (2015). Exploiting text and network context for geolocation of social media users. In: NAACL HLT 2015 - 2015 Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Proceedings of the Conference. NAACL HLT 2015 - Conference of the North American Chapter of the Association for Computational Linguistics: Human Language Technologies, Denver, Colorado, United States, (1362-1367). 31 May - 5 June 2015.

  • Rahimi, Afshin, Cohn, Trevor and Baldwin, Timothy (2015). Twitter user geolocation using a unified text and network prediction model. In: ACL-IJCNLP 2015 - 53rd Annual Meeting of the Association for Computational Linguistics and the 7th International Joint Conference on Natural Language Processing of the Asian Federation of Natural Language Processing, Proceedings of the Conference. 53rd Annual Meeting of the Association for Computational Linguistics and the 7th International Joint Conference on Natural Language Processing of the Asian Federation of Natural Language Processing, ACL-IJCNLP 2015, Beijing, China, (630-636). 26 - 31 July 2015.

  • Rahimi, Afshin, Sahlgren, Magnus, Kerren, Andreas and Paradis, Carita (2014). The STAVICTA group report for RepLab 2014 Reputation Dimensions task. In: CLEF 2014 Conference and Labs of the Evaluation Forum, Sheffield, United Kingdom, (1519-1527). 15-18 September 2014.

  • Neshati, Mahmood, Alijamaat, Ali, Abolhassani, Hassan, Rahimi, Afshin and Hoseini, Mehdi (2007). Taxonomy learning using compound similarity measure. In: Proceedings of the IEEE/WIC/ACM International Conference on Web Intelligence, WI 2007. IEEE/WIC/ACM International Conference on Web Intelligence (WI'07), Fremont, CA, United States, (487-490). 2-5 November 2007. doi:10.1109/WI.2007.135